A method for adjusting the running dynamics system and braking pressure for a wheeled vehicle.

Abstract

This relates to a driving dynamics system and a method for adjusting braking pressure. [Solution] The present invention relates to a driving dynamics system comprising at least one electric traction motor and at least one (first) electro-hydraulic pressure supply unit (BM1), wherein a primary control unit is communicably connected to a traction motor control unit for controlling the traction motor to execute steering and braking commands, and at least one of the hydraulically operable wheel brakes (RB1-RB4) is associated with a braking pressure regulating valve and outlet valve (AV1-AV4) in the form of a special solenoid valve (MV2k) particularly tensile resistant, wherein the driving dynamics system, in particular the primary control unit (M-ECU), is configured to selectively reduce pressure from at least one hydraulically operable wheel brake via the associated outlet valve or via the special solenoid valve (MV2k).

Description

Technical Field

[0001] name The present invention relates to a driving dynamics system (FDS) having a primary control unit or a central computer (M-ECU) described in the superordinate concept of claim 1, and a method for adjusting braking pressure.

[0002] Conventional technology Since the market introduction of the anti-lock braking system (ABS), anti-slip regulator (ASR), and electronic stability program (ESP) in 1978, 1986, and 1995, the braking pressure control system for an electro-hydraulic brake (EHC) has been accepted based on a feedback method using pre-pressure via a master brake cylinder. In this case, pressure increase by choking with PWM is performed via an inflow valve, and pressure decrease is performed via time control of an outflow valve. Inside the structural unit, usually, a valve block, an electric motor, a pump, an accumulator chamber, eight solenoid valves (for ABS) or twelve solenoid valves (for ESP), a pressure sensor, and an electronic control unit (ECU) are grouped together and assembled spatially separated from the brake booster in the engine room.

[0003] The most widely spread in the market in existing vehicles is the use of an ABS / ESP motor pump unit that combines a vacuum brake booster and a vacuum pump. There are a so-called two-box brake system having an electro-hydraulic brake booster and a spatially separated ESP unit (German Patent Application Publication No. 102012211278), and a so-called one-box brake system having an integrated brake booster and a pressure modulator (European Patent Application Publication No. 1907253, German Patent Application Publication No. 102013222281), which have become the standard in new vehicles.

[0004] The hydraulic structure of the ESP unit with 12 solenoid valves as a pressure supply unit has not been changed since the series introduction in 1995. However, due to the interaction between the control device of the electro-mechanical brake booster and the control device of the ESP unit for additional functions, and for the component protection of the more rigid electro-mechanical brake booster, a standardized interface (see VDA360) is defined. Therefore, for specific functions, the solenoid valves of the ESP unit for specific functions are driven and controlled via the control device. German Patent Application Publication No. 102012211278 describes the drive control of the valve for regenerative braking and the ABS pump.

[0005] The automotive industry is undergoing major changes. In addition to the increasing market penetration of electric vehicles, various levels of autonomous driving (SAE levels 2 - 5) are progressing, where the redundancy requirements for the braking systems used increase at each level of autonomous driving (see ATZ-Artikel 3 / 2019 “Bremskraftverstaerker fuer das automatisierte Fahren”).

[0006] Also, the central control device of the vehicle is introduced by a control device for chassis control (hereinafter also referred to as “vehicle motor control” or “VMC” or “vehicle chassis control” or “VCC”), which also includes an electro-hydraulic brake, electric traction motors (trademarks) at one or more axles of the vehicle, electric power steering (EPS), and a damping part as an optional means. By the central control device, the synergy can be fully utilized.

[0007] Since 2020, in Formula E racing series using powerful electric traction motors for regenerative braking, the "fade strategy" defined in Bremsenhandbuch 5.Auflage (see Kapitel 19: “Regenerative Brake Systems”), which reduces the hydraulic braking torque by the amount of the electric traction motor's braking torque, has finally been abandoned. Instead, additional braking torque is generated by the electric traction motor and the electro-hydraulic brake, thereby achieving a reduction in the time to lock braking torque / lock braking pressure (abbreviated as TTL). Consequently, braking distance is shortened by increasing braking torque as quickly as possible.

[0008] Current limitations and issues of conventional ABS / ESP systems A problem with current ABS / ESP braking systems equipped with motor pump units is that their dynamics are limited for newer functions such as automatic emergency braking (AEB). For these functions, it is crucial to generate braking pressure up to wheel lock pressure (typical values ​​in passenger car braking systems: 80-100 bar) in the shortest possible time. While ABS / ESP braking systems with pumps and electric brush motors reach 50 bar of pressure in 450 ms, a one-box brake system with a high-power brushless motor (German Patent No. 102005063659) can reach 80-100 bar of wheel lock pressure in less than 150 ms. A shorter TTL time can mean a reduction of over 5 meters in braking distance when the initial speed is 65 km / h.

[0009] Each ABS / ESP braking system (ABS / ESP braking system with motor pump unit and one box) has a check valve in its basic configuration. For safety reasons, these check valves are hydraulically connected in parallel to the inlet valve in the hydraulic pipeline to the wheel brakes, ensuring that the pressure in the wheel brakes is always automatically reduced, i.e., that no pressure remains in the wheel brakes in the event of a pressure supply failure. However, the technical solution here leads to difficulty or inability to diagnose wheel brake circuit failures because it is unclear whether the check valve or inlet valve is the cause of the wheel circuit failure. As a result, in error cases, the entire brake circuit, including both wheel brakes, must be deactivated. Therefore, a diagonal division of the brake circuit (X brake circuit) is the preferred division in most vehicles because, even in the event of a brake circuit failure, braking is still possible by the front wheel brakes, which have a greater braking force than the rear wheel brakes. The so-called "black and white" brake circuit (Type II brake circuit) in hybrid or electric vehicles has the disadvantage of reduced braking performance in error cases, but it has the advantage of making it easier to implement control strategies for regenerative braking.

[0010] Furthermore, ABS / ESP braking systems equipped with a motor pump unit that reduces pressure via a time-controlled outlet valve have disadvantages in terms of braking distance control performance compared to the aforementioned one-box braking system that reduces pressure into a storage container (see German Patent Application Publication No. 102013222281). This is because the back pressure (up to 5 bar) in the storage container during depressurization limits rapid depressurization at low pressures. This causes slow depressurization in the case of ABS control on roads with low friction values ​​(i.e., low μ) (such as ice or snow), resulting in a very long time for wheel speed reduction during ABS control. This leads to a long braking distance. On roads with partially extremely low friction values ​​(ice), ABS can only provide minimal control. Therefore, standard ABS / ESP systems have significantly more serious disadvantages in terms of control operation and braking distance due to their inferior control performance compared to the new standard set by the one-box braking system.

[0011] Problems of the invention The object of the present invention is to provide an improved running dynamics system, particularly a running dynamics system in the form of multiple pressure supply units (a two-box solution comprising two separate hydraulic pressure supply units hydraulically connected in series, each with a separate pressure actuator for two wheel brakes). Preferably, the system solves the problems described above. The system is also desirable to be compact, reliable, accurate, dependable, and highly efficient.

[0012] Furthermore, it is desirable that the driving dynamics system meets the requirements of autonomous driving modes (SAE stages 3 and 4 with driver intent detection via the E-pedal, or SAE stage 5 without pedals with target value setting by the central computer) and provides new interfaces between brake modules or between pressure supply units and / or between brake modules and the central computer.

[0013] Furthermore, it is desirable that the system incorporate at least one electric traction motor to efficiently provide driving dynamics control (ABS, ESP, EBV, ACC, AEB, regenerative braking management) and individual braking torque intervention for each wheel (BtS: Brake-to-Steering, BtTV: Brake-to-Torque Vectoring).

[0014] Solution of the invention The above problems are solved by the subject matter described in claim 1.

[0015] In particular, the above problem relates to a driving dynamics system for a vehicle equipped with wheels, - A primary control unit that detects and / or forms steering commands and braking commands, -At least two hydraulically operated wheel brakes, each associated with one wheel, - An electric traction motor comprising a traction motor control unit, wherein the traction motor is positioned to drive at least one of the wheels, wherein The primary control unit is communicatively connected to the traction motor control unit in order to control the traction motors in order to execute steering and braking commands. At least one electric traction motor, - At least one (first) electrohydraulic pressure supply unit, • At least one electric motor pump unit, • At least two terminals for connecting the wheel brakes, • Electrically operated wheel brake pressure regulating valve or brake pressure regulating valve, • First secondary control unit A (first) electrohydraulic pressure supply unit comprising Equipped with, At least one of the hydraulically operated wheel brakes (RB1-RB4) is associated with a braking pressure regulating valve and an outlet valve in the form of a special solenoid valve particularly resistant to tension. In the driving dynamics system, The driving dynamics system, particularly the primary control unit (M-ECU), is configured to selectively reduce pressure from at least one hydraulically operated wheel brake via an associated outlet valve or a special solenoid valve (MV2k). This is resolved by a driving dynamics system characterized by the following:

[0016] Preferably, in the first modified configuration, pressure reduction is performed exclusively through each outlet valve. In the second modified configuration, pressure reduction can be performed only through each special solenoid valve, or simultaneously through both the special solenoid valves and the outlet valves.

[0017] Furthermore, the above challenges are, - A primary control unit that detects and / or forms steering commands and braking commands, -At least two hydraulically operated wheel brakes, each corresponding to one wheel, - A traction motor control unit is provided, and at least one electric traction motor is positioned to drive at least one of the wheels, wherein, The primary control unit is communicatively connected to the traction motor control unit in order to control the traction motors in order to execute steering and braking commands. Electric traction motor and, - At least one (first) electrohydraulic pressure supply unit, • At least one electric motor pump unit, • At least two terminals for connecting the wheel brakes, • Electrically operated wheel brake pressure regulating valve or brake pressure regulating valve, • First secondary control unit A first electro-hydraulic pressure supply unit equipped with Equipped with, - At least one of the braking pressure regulating valves includes a special solenoid valve equipped with an electromagnetic drive device having a first excitation coil, wherein a valve operating member or valve tappet is displaceable between a valve open position and a valve closed position via the first excitation coil. This is resolved by the driving dynamics system.

[0018] An aspect of the present invention is that the special solenoid valve has a force-applying device comprising a permanent magnet and / or a second excitation coil, arranged to form at least one holding force acting on a valve actuator or valve tappet. Preferably, the special solenoid valve, which can be used as an inlet valve or a wheel inlet control valve, is tensile-resistant by the above measures.

[0019] By designing a wheel brake circuit using a wheel inlet control valve with tensile strength, the system of the present invention has significantly higher error tolerance than conventional brake devices, and can implement a brake system having multiple wheel circuits (individual pressure control devices and / or pressure supply devices for each wheel) instead of conventional (diagonal or black and white) brake circuits for multiple wheels. For example, a wheel circuit failure can be diagnosed, and the failed wheel circuit can be isolated from the pressure supply device by closing the inlet valve. This allows for significantly improved deceleration even in the error case by the remaining three wheel circuits when an (individual) wheel circuit fails, and enables further yaw moment intervention by the three wheels. Hereinafter, the brake module of the first pressure supply unit equipped with the special solenoid valve described in claim 1 will be referred to as ESP-X.

[0020] The detection of steering and / or braking commands by the primary control unit can be performed, for example, via a steering wheel sensor or force displacement sensor in the E-brake pedal. However, the primary control unit can also be configured to generate independent steering and braking commands, which is essential in the process of autonomous driving. Similarly, corresponding commands may arise based on the implementation of safety functions (e.g., automatic emergency braking). In the sense of this invention, a steering command does not refer to specific driver intervention using the steering wheel. Rather, in this invention, a steering command is understood to mean any instruction that moves the vehicle in a specific direction and also relates to trajectory control during autonomous driving mode. For example, a steering command here also includes a command that causes a change in yaw moment. Torque vectoring can also be implemented by corresponding steering and / or braking commands.

[0021] The (first) electro-hydraulic pressure supply device may be an ABS / ESP unit. However, it should generally be understood as any unit having a pressure generator, for example, in the form of the motor pump unit described above, and forming the corresponding pressure at the corresponding terminals. The pressure supply unit can also perform closed-loop control and / or open-loop control functions. Therefore, these can be made into a pressure regulation module.

[0022] One aspect of the present invention involves a special solenoid valve that generates an additional holding force. This gives the special solenoid valve tensile resistance, allowing it to reduce high pressures. In addition to the holding force, it can also generate a return force that moves the valve actuator or valve tappet to the valve open position.

[0023] In one embodiment, the primary control unit can be configured to drive and control a special control valve in at least one of the selected braking modes such that the pressure is reduced when the special solenoid valve associated with the wheel brake of the first pressure supply unit is released. Preferably, each special solenoid valve is associated with the first pressure supply unit of the wheel brake. Based on a tensile-resistant configuration, each special solenoid valve can be used not only as an inlet valve but also as a kind of outlet valve. The pressure can be increased or decreased bidirectionally through the same special solenoid valve. Thus, (significantly) rapid pressure reduction of the respective associated wheel brakes can be enabled because the pressure can be reduced through both the multiple valves (special valves) and the outlet valve. Furthermore, the pressure in the wheel brake can be maintained by closing the valve while the pressure in the wheel brake is high, with the pressure generator driven at low pressure. This provides a new degree of freedom that is extremely advantageous for the primary control unit in the central control strategy.

[0024] In one embodiment, at least one of a plurality of wheel brakes associated with a special solenoid valve also has a discharge valve. The corresponding discharge valve can be assigned to the wheel brake. In one embodiment, the discharge valve and the special solenoid valve are used simultaneously for pressure reduction, thereby reducing the pressure in each wheel brake as quickly and effectively as possible. In particular, the primary control unit can be configured to simultaneously drive and control the associated special solenoid valve and the discharge valve in at least one of the selected braking modes, so that brake fluid is simultaneously discharged from the wheel brake through the associated special solenoid valve and the associated discharge valve.

[0025] In one embodiment, the driving dynamics system has at least one second pressure supply unit. Preferably, the second pressure supply unit includes a piston cylinder unit or a rotary pump, i.e., a unique pressure generator. The second pressure supply unit is connectable to at least one input side of the first pressure supply unit to supply brake fluid. In one embodiment, the pressure supply unit not only functions as a pressure reservoir but also as a pressure sink (open-loop controllable / close-loop controllable) or alternatively has at least one valve for pressure reduction (e.g., a central outlet valve, see International Publication No. 2020165259, an outlet valve of an ABS / ESP unit). When an inlet valve of an ABS / ESP unit is used for pressure reduction, the pressure reduction is time-controlled by the valve, but PWM control is also possible. For example, when a piston cylinder unit is used, by pulling back the cylinder in the piston, a very low pressure, e.g., 1 bar to 5 bar, can be generated, in which case the resulting pressure difference results in rapid pressure reduction in the wheel brakes. In a (preferred) embodiment, the pressure supply unit supplies brake fluid for a first brake circuit and a second brake circuit, where preferably, at least one separation valve is provided to separate the first brake circuit and / or the second brake circuit. The separation valve here can be configured similarly to or identical to the special solenoid valves already described, as will be described in more detail below.

[0026] Furthermore, multiple first pressure supply units can be provided and connected to a second pressure supply unit.

[0027] In one embodiment, the first pressure supply unit is directly connected to exactly two wheel brakes. Preferably, these two wheel brakes correspond to each wheel on the first axle. In one embodiment, in addition to the first pressure supply unit, there is also at least one other pressure supply unit directly connected to at least two wheel brakes on the second axle. In other words, this other pressure supply unit supplies pressure to two wheel brakes corresponding to each wheel on the second axle. That is, according to the present invention, a plurality of first pressure supply units can be provided as different modules, in which case each module corresponds to each module on a particular axle, or to a wheel brake on a particular axle. Depending on the vehicle, pressure supply units can be provided on other axles in addition to the first and second axles, in which case each pressure supply unit on one axle is preferably communicably connected to a primary control unit to receive steering and braking commands. According to the present invention, a direct connection between one device and another should be understood as a hydraulic connection via a pipeline that is not interrupted by other devices, such as a valve or a pressure generator.

[0028] In one embodiment (hereinafter also referred to as valve terminal variation I), a special solenoid valve is configured in a conventional ABS / ESP device, which typically has an armature chamber connected to the wheel brake and a valve seat connected to a pressure supply unit, and is open when de-energized. The pressure can be increased via pre-pressure control and PWM control of one or more special solenoid valves. Pressure reduction is performed via time control of the same valve, and there is no risk of the special solenoid valve being pulled during pressure reduction, based on its tensile resistance configuration.

[0029] In another embodiment (valve terminal variation II), the valve seat of at least one special solenoid valve is connected to a wheel brake. This arrangement makes it possible to reduce the pressure in each corresponding wheel brake with low noise. Based on this arrangement, the valve opening cross section can be adjusted, in particular by PWM drive control or current closed-loop control. In this way, choked pressure reduction can be performed via the special solenoid valve. In this embodiment, pressure boosting via the special solenoid valve can be performed via time control or volumetric adjustment, which can be performed within a second pressure supply unit, for example, by adjusting the rotation angle of a rotary pump or adjusting the stroke of a piston in a piston cylinder unit.

[0030] The two terminal shapes allow the wheel brakes to be disconnected from the system by simply closing them with current supplied to a special solenoid valve. To maintain the special solenoid valve, a low holding current should be applied. This disconnection can be advantageous if a defect, such as a leak, is detected within each wheel brake.

[0031] In one embodiment, the first supply unit may include a rotary pump connected and configured to increase or decrease the pressure in the wheel brake. This allows the rotary pump to function as a pressure sink and perform rapid depressurization.

[0032] Furthermore, the above challenges are related to the driving dynamics system, - A primary control unit that detects and / or forms steering commands and braking commands, -Four hydraulically operated wheel brakes, each corresponding to a wheel, - A traction motor control unit is provided, and at least one electric traction motor is positioned to drive at least one of the wheels of the vehicle, wherein, The primary control unit is communicatively connected to the traction motor control unit to control the traction motors in order to execute steering and braking commands. At least one electric traction motor, -At least one first electrohydraulic pressure supply unit, • At least one electric motor pump unit, • At least two terminals for connecting the wheel brakes, • Electrically operated wheel brake pressure regulating valve or brake pressure regulating valve, • First secondary control unit A first electro-hydraulic pressure supply unit comprising, - To supply brake fluid to at least one input side of the first pressure supply unit, at least one second electrohydraulic pressure supply unit is provided for the first brake circuit and the second brake circuit, and Equipped with, The second pressure supply unit is associated with at least one isolation valve in the form of a special solenoid valve for isolating the first brake circuit and / or the second brake circuit. The special solenoid valve includes an electromagnetic drive device equipped with a first excitation coil, and via the first excitation coil, the valve operating member or valve tappet of the special solenoid valve is displaceable between the valve open position and the valve closed position. This is resolved by the driving dynamics system.

[0033] Alternatively, the above problems can be solved by a system for a vehicle equipped with wheels (R1-R4), particularly a driving dynamics system, as described in the earlier embodiments. This system is - A primary control unit (M-ECU) that detects and / or generates steering commands and braking commands, -Four hydraulically operated wheel brakes (RB1-RB4), each corresponding to a wheel (R1-R4), -Equipped with a traction motor control unit (S-ECU-TMHA), at least one electric traction motor (TM1, TM2) is provided, wherein the traction motor (TM1, TM2) is arranged to drive at least one of the vehicle's wheels (R1~R4), and here, The primary control unit (M-ECU) is communicatively connected to the traction motor control unit to control the traction motors (TM1, TM2) in order to execute steering and braking commands. At least one electric traction motor (TM1, TM2) and -At least one first electrohydraulic pressure supply unit (BM1), • At least one electric motor pump unit, • At least two terminals for connecting the wheel brakes (RB1~RB4) • Electrically operated wheel brake pressure regulating valve or brake pressure regulating valve, • First secondary control unit (S-ECU1) A first electro-hydraulic pressure supply unit (BM1) is provided, - To supply brake fluid to at least one input side of the first pressure supply unit, at least one second electrohydraulic pressure supply unit (BM2) is provided for the first brake circuit (BK1) and the second brake circuit (BK2), and It can be equipped with, The second pressure supply unit (BM2) is associated with at least one isolation valve (TV1, TV2) in the form of a special solenoid valve (MV2k) that isolates the first brake circuit (BM1) and / or the second brake circuit (BM2). The special solenoid valve (MV2k) includes an electromagnetic drive device equipped with a first excitation coil (SP1a), and the valve operating member (7) or valve tappet (7a) of the special solenoid valve (MV2k) is displaceable between the valve open position and the valve closed position via the first excitation coil (SP1a).

[0034] The above system can be characterized in that the special solenoid valve (MV2k) has tensile resistance by providing a force-applying device which includes a permanent magnet (PM) and / or a second excitation coil (SP1b, SP2) and is arranged to form at least one holding force (FPM, FEM2) acting on the valve operating member (7) or valve tappet (7a).

[0035] One aspect of the present invention is that a special solenoid valve has tensile resistance by providing a force-applying device which includes a permanent magnet and / or a second excitation coil and is arranged to form at least one holding force acting on a valve operating member or valve tappet.

[0036] In other words, the special solenoid valve can also be used as a separation valve, for example, as part of a second pressure supply unit (hereinafter also referred to as the second brake module BM2). In this case, the second brake module BM2 does not need to include a separation valve if only hydraulic terminals to the first brake module (Figures 9, 10, and 15) exist, and even in embodiments without a separation valve, it is still referred to as brake module BM2. Tensile resistance also brings about a significant improvement to the system in this case. Generally, according to the present invention, other valves with comparable tensile resistance can also be used. Such a system is preferably a two-box system in which the first pressure supply unit is part of the first box and the second pressure supply unit is part of the second box.

[0037] When a special solenoid valve having the aforementioned permanent magnet and / or second excitation coil is used, the special solenoid valve can be configured similarly to or identical to that already described above. In addition to the holding force described above, the force-applying device can also additionally generate a return force.

[0038] By advantageously utilizing a second pressure supply unit for pressure reduction at low friction values, even low-cost ABS / ESP braking systems can achieve new levels of control quality, making them fully competitive in terms of braking distance performance with the novel one-box braking system (German Patent Application Publication No. 102013222281, Bremsenhandbuch 5.Auflage, Kapitel 20.3 “Integriertes Bremssystem MK C1”).

[0039] Independent of the configuration of the second pressure supply unit, in one embodiment, the first pressure supply unit can be equipped with a rotary pump that increases and decreases pressure according to the rotation direction of the rotary pump, thereby providing greater flexibility in pressure reduction. Furthermore, in this embodiment, based on the absence of back pressure in the storage chamber, the pressure during ABS operation at low friction values ​​("low μ") can be effectively reduced. This results in a highly accurate and low-cost system.

[0040] In another embodiment, the first pressure supply unit can be configured to reduce pressure into the storage container rather than into the storage chamber. This is possible based on the high safety gain achieved by the special solenoid valve according to the present invention, particularly when used as an inlet valve, and significantly improves ABS control performance.

[0041] In one embodiment, along with electric traction motors on one or more axles, braking torque via the electric traction motors and pressure in a first and / or second pressure supply unit are formed simultaneously. In connection with this, when pressure is increased, electric braking force distribution (EBV) can be performed by the first and / or second pressure supply unit to prevent the rear wheels from locking before the front wheels. When the wheel lock pressure is reached, ABS control can be used according to the present invention, and the braking torque of at least one traction motor is reduced very rapidly. The corresponding behavior does not pose a safety risk for electric traction motors driven at high voltages (>400V, especially >700V) and with a braking torque gradient of >10000Nm / s, and functions sufficiently quickly, possibly already in the first control cycle, for safe braking torque reduction. According to the present invention, this is made possible by the introduction of a central driving dynamics control unit (FDS), which synchronously drives and controls the electric traction motor TM and the pressure generator unit, and recognizes ABS cases very quickly by evaluating the wheel rotation speed sensor. For this purpose, the primary control unit can be communicatively connected to the wheel rotation speed sensor so that it can directly read the corresponding sensor values. With the approach of the present invention, even in automatic emergency braking, a TTL of 150 ms can be achieved by pressure formation via the pump of the first brake module BM1 alone, whereas until now, comparable values ​​could only be expected in a one-box brake system with a high-power brushless motor.

[0042] Alternatively or additionally, according to the present invention (in addition to the electric traction motor), a 6-piston pump or a higher-power brush motor can also be used in the first pressure supply unit, thereby achieving a shorter TTL time. According to this approach, even a lower-power electric traction motor can achieve a good TTL time, in some cases as low as 150 ms. According to the present invention, the individual means of the one-box concept embodiment can be combined in various ways.

[0043] The pressure supply unit can be configured for both pressure boosting and pressure reduction. The first and second pressure supply units may each have one secondary control unit having at least one communication interface. The communication interface can be used to establish communication with the primary control unit. In particular, measurement signals and operating target values ​​can be exchanged. The special solenoid valve of the second pressure supply unit can be configured such that the valve seat of the special solenoid valve is (directly) connected to the input side of the first pressure supply unit (valve terminal variation III). Based on the configuration of the special solenoid valve, the valve opening cross section can be adjusted in particular by PWM drive control or current closed-loop control. With such special configurations, in this case as well, pressure can be choked from the first pressure supply unit via the special solenoid valve, and thus the pressure can be reduced with low noise. In this configuration, pressure boosting is preferably performed by time control or volumetric metering (see the above description of pressure open-loop control / pressure closed-loop control via volumetric metering).

[0044] In one embodiment, the primary control unit is configured to perform individual pressure control for each wheel brake or each brake circuit by driving and controlling at least one special solenoid valve of a first pressure supply unit and / or at least one second pressure supply unit.

[0045] In one embodiment, the primary control unit is configured to detect a wheel circuit fault by pressure measurement when a special solenoid valve of the first pressure supply device or inlet valve is closed. A corresponding diagnostic method may include measuring the pressure present in the system to see if the pressure drops even though all the relevant valves are closed. If the pressure drops, a leak can be assumed to be present. By closing the special solenoid valve, further pressure can be increased in the remaining brake circuit or other wheel circuits that do not have leaks. For example, the pressure can be increased by piston movement in a second pressure supply unit. If there is no pressure increase correlated with piston movement, the leak location can also be estimated in this case.

[0046] As already described, the primary control unit can be configured to isolate a faulty brake circuit by closing at least one of the isolation valves. That is, in a preferred embodiment, the faulty brake circuit or wheel brake circuit can be shielded and the remaining system can be isolated individually for each wheel circuit or each brake circuit.

[0047] The primary control unit can be configured to perform ABS (per axle) by controlling at least one of the isolation valves and by (alternating) pressure boosting and depressurizing via a second pressure supply unit. That is, unlike conventional systems, the second pressure supply unit can be used to perform at least one (minimum) 1-channel ABS. This provides additional redundancy.

[0048] In one embodiment, the primary control unit is configured to perform (automatic) emergency braking by parallel drive control of a traction motor and at least a first pressure supply unit. A corresponding control strategy can also be achieved with a single traction motor.

[0049] The primary control unit controls the electric traction motor and electro-hydraulic brakes to enable (automatic) emergency braking (AEB) or increased braking torque, especially for high braking torques (>3 m / s). 2 It can be configured to perform a high deceleration (>5 m / s) of the vehicle when emergency braking is performed. 2 Preferably, up to the maximum deceleration (>8 m / s) 2 , especially >9.5 m / s 2 ) are formed additively. The ABS situation can be identified by evaluating the wheel rotation speed sensor during the emergency braking function, i.e., during a highly dynamic pressure increase. In this case, the primary control unit can reduce (from the center) the braking torque of the electric traction motor and / or electro-hydraulic brake or the vehicle axle on one or more locked wheels.

[0050] In one embodiment, the first electromagnetic drive device comprises at least one first solenoid valve drive mechanism and a second solenoid valve drive mechanism, where a secondary control unit is communicatively connected to the first solenoid valve drive mechanism to control at least one special solenoid valve, and a primary control unit is communicatively connected to the second solenoid valve drive mechanism to control at least one special solenoid valve. This means that the special solenoid valve is actuated by two separately configured control devices, thereby ensuring continued operation of the special solenoid valve even if one of the control devices fails. The communicative connection here may be an electrical connection.

[0051] In one embodiment, the primary control unit is configured to adjust the braking pressure at least temporarily in the selection of brakes in the multiplex method / PCC method, where the primary control unit provides an adjustment signal to a second pressure supply unit to increase or decrease the pressure.

[0052] In one embodiment, a communication interface Int-BM1, Int-BM2 is provided between the central computer or primary control unit and the control unit of the brake module (BM1 or BM2), and another interface Int is provided between the control devices of the two brake modules S-ECU1 and S-ECU2. 2BM A new FDS architecture is achieved, having the following: Interface Int-2BM is incorporated into the VDA360 standard, which is defined as an interface for cooperation between an electric follow brake booster (e.g., i-Booster product) and an ESP-hev brake system for regenerative braking, and in particular as an interface for valve operation of the outflow valve of the ESP-hev system. Furthermore, the FDS incorporates at least one electric traction motor (TM1, TM2, TM3). At least one other interface is provided between the central computer and the traction motors, preferably one interface IntTMi between the M-ECU and each traction motor's secondary control unit (S-ECU-TMi), or between the M-ECU and each axle's control unit (IntTM) of the vehicle, especially if the axle includes multiple traction motors. HA IntTM VA An interface is provided between the two. Such a configuration is advantageous, for example, when the rear axle has one traction motor for each wheel in order to accelerate or brake each wheel individually.

[0053] One or more of the communication interfaces may be an electrical connection, a cableless connection, or an optical connection, in which case preferably two communication paths are selected. The first communication path can be configured redundantly, and the second communication path can be used to inspect the signals of the first communication path. In one embodiment, the signal transmission system 2 is implemented in a 2-Out-of-3 scheme using two different signal transmission types in order to satisfy the requirements for SAE Level 5 and to further eliminate errors in transmission. A 2-Out-of-3 braking system must be maintained in a braking device for SAE Level 4 using an E-pedal or SAE Level 5 that does not necessarily use a pedal, because driver intervention via the brake pedal is no longer available.

[0054] Additionally, the primary control unit can also drive and control the solenoid valve driver of the inlet valve of the first pressure supply unit. This allows for individual pressure control for each wheel for steering functions, particularly 4-channel ABS or individual braking torque intervention for each wheel, to be performed by the second pressure supply unit and special solenoid valves, exclusively in the wheel brakes, independently of the operation of the pressure generator, e.g., the pump, and the secondary control unit of the first pressure supply unit. In one embodiment, the solenoid valve drivers, particularly the special solenoid valves, are configured redundantly.

[0055] In one embodiment, the secondary control device of the first pressure supply unit is provided with a solenoid valve electronic circuit that is galvanically separated from the main control board. This solenoid valve electronic circuit is supplied with a specific voltage, thereby enabling it to operate autonomously. As a result, even if the first pressure supply unit completely fails, complete ABS can be achieved.

[0056] Furthermore, centralized driving dynamics control within the domain of the central computer can be easily achieved by a chassis control system incorporating steering actuators, such as an electric power steering system and an electric traction motor. The existing software architecture can be substantially maintained, and higher-level additional functions requiring cooperation between the steering actuators and the electric traction motor can be easily implemented, for example, within the primary control unit. In one embodiment, the functions of the first pressure supply unit are transferred to the primary control unit, so the first pressure supply unit is configured solely as a pressure actuator.

[0057] The FDS (Functional Dynamics System), as a central vehicle dynamics control system, may include several of the following components: - A primary control unit (M-ECU) that detects and / or generates steering commands and braking commands, wherein, The primary control unit has at least one of the following functions: ABS, ESP, ASR, ACC, AEB, regenerative braking, and steering with redundant microcontrollers μC1, μC2, and μC3. Primary control unit (M-ECU), -Each of the secondary control units (ECU-TM1, ECU-TM2, ECU-TM3) or axle control units (ECU-VA, ECU-HA) includes at least one electric traction motor TM1, TM2, TM3 that drives and brakes the wheels, - At least one brake module (BM1) having hydraulic terminals for multiple wheel brakes, - A central vehicle model capable of calculating steering and braking commands considering the friction value of the road surface, vehicle speed, and / or dynamic weight distribution during braking, wherein, For braking and steering, at least a wheel rotation speed sensor, preferably another sensor (accelerometer and / or weight sensor), is read into the primary control unit. The central vehicle model and Includes.

[0058] The FDS (Fast Distance Dynamics) system uses a primary control unit (M-ECU) to generate steering and braking commands for braking torque modulation (e.g., ABS, ESP, EBV). - The basic braking torque is formed by an electric traction motor or brake module BM1 or BM2, and the braking torque modulation (e.g., ABS, ESP) is controlled in a closed loop via the electric traction motor, or - The braking torque modulation is adjusted in common by at least one electric traction motor and at least one brake module (BM1 or BM2), or - Braking torque modulation on the rear axle is controlled in a closed loop via an electric traction motor, and braking torque modulation on the front axle is controlled in a closed loop via at least one electro-hydraulic brake module (BM1, BM2). It is characterized by being transmitted to multiple secondary control devices.

[0059] FDS can be advantageously utilized to optimize regeneration and brake output in various driving conditions with respect to braking situations (comfort braking, emergency braking), road characteristics (braking on asphalt, snow, ice, μ-jumps, μ-splits), and brake module availability. Furthermore, it is desirable that the cost of brake calipers be reduced even when the deceleration is large (<5 m / s) through control via FDS and regenerative braking via electric traction motors. Regenerative braking minimizes the thermal load on friction brakes, allowing for a reduction in the use of disc brakes on the front axle or the use of drum brakes on the rear axle.

[0060] Thus, during braking torque modulation, at least one brake module (BM1, BM2) and at least one electric traction motor (TM1, TM2, TM3) are simultaneously driven and controlled via a central primary control unit, and the braking torque command is divided between at least one brake module and at least one electric traction motor.

[0061] In an embodiment of a brake system comprising at least one brake module (BM1, BM2) and a special solenoid valve preferably directly driven and controlled via a primary control unit, individual braking torque intervention can be performed for each wheel by control via the primary control unit. According to the present invention, in the event of a wheel circuit failure, the remaining wheel circuits can continue to be driven by closing the special valve of the failed wheel brake circuit. Furthermore, the time to live (TTL) can be minimized by driving and controlling at least one traction motor and at least one brake module from a central source.

[0062] In particular, these embodiments provide the following functions, namely, • Automatic emergency braking (AEB) with high dynamics (50ms~180ms) through common braking torque intervention via electric traction motor and brake module. • Individual braking torque intervention for each wheel for steering assistance (Brake to Steer, BtS) or driving dynamics (Brake to Torque Vektoring, BtTV), • Vehicle stabilization when yaw rate is large (ESP function) • Individual regenerative braking for each wheel or each axle Therefore, advantages can be obtained.

[0063] According to the present invention, starting from a two-circuit ABS / ESP braking system, new functions and improved failure prevention can be achieved by changing the hydraulic structure and replacing fewer components. Thus, a three-circuit or four-circuit braking system with significant safety advantages is provided. The vehicle dynamics system FDS can further perform individual braking torque control for each wheel via a pressure interface Int-BM1 to the primary control unit, in which case individual braking torque control for each wheel or each axle can be more easily implemented via the pressure interface than in the case of a standard ESP unit. The system according to the present invention can further adjust the pressure in each wheel brake more accurately and dynamically. By using the system of the present invention, individual braking torque intervention for each wheel can always be performed in three wheel brakes, which results in significant advantages in vehicle stabilization functions and a highly dynamic process, such as AEB with electronic brake force distribution (EBV).

[0064] Furthermore, the driving dynamics system satisfies the SAE Stage 3-5 autonomous driving redundancy requirements (redundant brake boosters, redundant ABS function, and redundant EBV function). The system can operate using two pressure supply units (a so-called two-box brake system with one pressure supply unit each) in cooperation with an external pressure generator DV2 and a low friction value (i.e., low μ) ESP-X unit in addition to redundant ABS / ESP function, so that the control performance, especially as part of the pressure supply unit, is significantly improved compared to conventional technology. By favorably integrating a central computer in the form of a primary control unit into the domain architecture of the E-vehicle, the emergency braking function AEB should be further improved by synchronized target setting of braking torque to the control devices of one or more electric traction motors. Thus, TTL can be significantly shortened.

[0065] After the braking torque of the electric traction motor acts on one vehicle axle or on multiple vehicle axles with different braking torques, it is necessary to further control the braking force distribution (EBV), that is, to distribute the hydraulic braking torque to the front and rear axles in a manner different from the braking torque in standard EBV control. The system of the present invention can prevent the rear axle wheels from locking before the front axle wheels, and the front axle wheels from locking only at a deceleration of 0.85g. In the case of wheel lock, ABS intervenes, and in the case of ABS control, the braking torque of the electric traction motor must be taken into consideration.

[0066] One embodiment of the driving dynamics system according to the present invention may be characterized by replacing at least two, preferably four, inlet valves of a first pressure supply unit with special solenoid valves that are open when de-energized. Unlike the prior art, the tensile-resistant special solenoid valves do not have check valves located in a hydraulic path parallel to the inlet valves or check valves incorporated within the inlet valves. As already stated in the prior art problem statement, check valves are used to ensure a more reliable reduction of braking pressure from the wheel brakes in the event of brake failure or partial failure of the brake system, such as the pressure supply unit. However, this can be omitted in the system according to the present invention.

[0067] The problem mentioned at the beginning can be further solved by a switching valve. This switching valve can be used in particular in relation to the travel dynamics system already described. On the one hand, this switching valve can be used in the function of an inlet valve (ESP device), and on the other hand, in the function of a separation valve for a second pressure supply unit.

[0068] The switching valve is, - Valve operating member or valve tappet, - Armature connected to valve operating member or valve tappet, - An electromagnetic drive mechanism comprising at least one excitation coil for displacing a valve tappet along the longitudinal direction between a valve open position and a valve closed position, It can include...

[0069] A switching valve may be characterized in that the armature has at least one permanent magnet. In one embodiment, the permanent magnet is positioned such that the valve actuating member or valve tappet is held in the open position by the magnetic force formed by the permanent magnet. Preferably, the magnetic force acts even when there is no power supplied to the electromagnetic drive. This provides the switching valve with special tensile strength, particularly when a volumetric flow travels through the valve.

[0070] The switching valve described above can be used as a special solenoid valve in the sense of the present invention, similar to the embodiment of the switching valve described below.

[0071] In one embodiment, the armature contains at least one ring-shaped permanent magnet or a plurality of permanent magnets. The ring-shaped magnet or the plurality of permanent magnets may have magnetic pole directions that extend substantially perpendicular to the longitudinal direction.

[0072] In one embodiment, one or more permanent magnets are embedded axially and radially within a material having ferromagnetic conductive properties.

[0073] In one embodiment, a permanent magnet (PM) and / or an adjacent ferromagnetic flux guide block are positioned and dimensionally designed such that, when the electromagnetic drive is de-energized, the magnetic force displaces the valve tappet from the valve closed position to the valve open position. That is, the valve is a valve that opens automatically in the event of a power outage. This has the special advantages already described, particularly in relation to the aforementioned travel dynamics system.

[0074] The electromagnetic drive device may include a first excitation coil and at least one second excitation coil. That is, preferably, there are redundant excitation coils connected to a separately configured solenoid valve driver. This very generally enhances the fault safety of the valve. Furthermore, the valve can be separately connected to different control units, for example, one of the secondary control units and one of the primary control units. Therefore, one of the two control units can take over control via the valve if the other control unit fails.

[0075] In one embodiment, four switches, particularly an H-bridge including power semiconductors, are provided, each capable of forming an electromagnetic field with a different polarity. As a result, when the excitation coil is energized, the valve can be actively opened and closed according to the H-bridge connections and the resulting current direction through the excitation coil. This allows operation during both pressure increase and pressure decrease by adjusting the current using a variable cross-sectional area, independently of the flow direction. The H-bridge allows the electric magnetic field to be reversed by at least one excitation coil, and further allows adjustment of the magnetic field strength. This enables closed-loop control of the force and amplitude on the armature (in the direction of action).

[0076] In an alternative embodiment, the switching valve advantageously provides a novel and simultaneously low-cost design according to the present invention, comprising a first soft iron magnetic circuit EM1 and a second magnetic circuit EM2 formed via a permanent magnet, wherein in one embodiment, the forces of the two magnetic circuits EM1 and EM2 act on the armature of the ball switching valve.

[0077] Some of the switching valves according to the present invention can be manufactured at low cost by using many of the components of a standard solenoid valve (e.g., an electromagnetic circuit having an armature diameter and coil) and changing only the end portion (head portion) of the valve.

[0078] In this way, a permanent magnet circuit is provided in the head portion, thereby integrating a soft iron electromagnetic circuit (EMI) and a second electromagnetic circuit (EM2) formed by a simple permanent magnet into a single valve. This embodiment has the significant advantage that existing manufacturing equipment can be used for production. In this way, the inlet valve can be easily replaced with the special solenoid valve using typical press-fit assembly techniques, preferably with an unchanged diameter and the same interface to the hydraulic block (HCU), i.e., the special solenoid valve can be easily inserted into an unmodified hydraulic block. Furthermore, the ECU (= secondary control unit), which is fitted over the hydraulic block and supports the excitation coil of the solenoid valve, can be modified completely or only slightly.

[0079] Generally, the aforementioned brake module BM1, which has a special solenoid valve (ESP-X), has the following diverse configurations (A to E): A) Configuration A :Brake module BM1 (e.g., as ESP-X) hydraulically connected to a vacuum brake booster, B) Configuration B For example, a brake module BM1 hydraulically connected to an electrically operated successor brake booster, as described in German Patent Invention No. 112009004636, C) Configuration C :Brake module BM1 hydraulically connected to an electro-hydraulic brake booster equipped with a pedal-sensitive simulator. D) Configuration D :Brake module BM1 is hydraulically connected to the second brake module BM2 and driven via the primary control unit and the E-brake pedal. E) Configuration E : A brake module BM1 as an autonomous pressure adjustment unit, driven via a primary control device, for example, as an axle module operating two wheel brakes, or a central hydraulic unit for operating four wheel brakes. Therefore, it is usable.

[0080] The use of special valves with tensile resistance (wheel brake circuits with separation means by closing special solenoid valves) is permitted in all configurations A to E. • Diagnosis of leaks by measuring the pressure increase or volumetric flow rate when the pressure supply unit increases pressure during valve closure. • Diagnosis of wheel brake circuit failures by measuring the pressure increase or volumetric flow rate when the valve is opened and comparing it with a typical pressure-volume characteristic curve of a wheel circuit that has been measured in advance and stored in memory. • Determining further operation of the wheel brake circuit when leakage is small. - Determination regarding the isolation of the brake circuit by the continuous closure of the valve connected to the faulty wheel brake circuit and the continuous operation of the three wheel brakes. • Selective pressure reduction via outlet valve or special solenoid valve, • Maintaining wheel braking pressure at low braking pressure in other wheel brakes, This makes it possible.

[0081] Furthermore, in the event of, for example, a failure of the excitation coil or a failure of the solenoid valve driver of an outflow valve that is closed in an unpowered state, the pressure can be reduced alternatively through the inflow valve, thereby increasing the usability of the FDS (Functional Dynamics System).

[0082] Special solenoid valves are particularly important in terms of function and safety, and it is advantageous for these valves to have a configuration that provides tensile strength, as well as additional redundant coils and solenoid valve drivers. In outlet valves that are closed when de-energized, such redundant means can be omitted for cost reasons, because pressure can still be reduced via the special solenoid valve even if the outlet valve fails. Thus, pressure boosting is guaranteed by the redundant means. This significantly reduces the probability of failure in the wheel brake circuit and allows the running dynamics system to operate with high reliability in all wheel brake circuits. The redundant means here are of great significance, for example, in individual braking torque control for each wheel for functions BtS and BtTV, and especially in central running dynamics control via the primary control unit.

[0083] Known pressure control methods may remain unchanged in one embodiment of the present invention, and pressure is increased via pre-pressure control of the inlet valve and driving using a variable valve opening cross-sectional area. The solenoid valve is driven as a proportional valve by current closed-loop control or current open-loop control (commonly referred to as PWM operation of the inlet valve among those skilled in the art).

[0084] In another embodiment, pressure control can utilize new degrees of freedom in the control strategy. This allows the central computer to implement functional improvements and new functions in ABS operation, such as individual braking torque intervention for each wheel via a pressure interface. New functions of the central driving dynamics control include, in particular, individual braking torque control for each wheel for torque vectoring (BtTV), braking torque intervention for yaw rate control of the ESP function, or steering function (BtS), and / or individual regenerative braking for each axle or each wheel.

[0085] In one embodiment (valve terminal variation I), the valve seat of the inlet valve, particularly the special solenoid valve, is connected to the brake circuit, and the armature chamber is connected to the wheel brake. Here, pressure control method A (= standard pressure adjustment mode or EV) is used.PWM / AV Δt - A pressure control method is used, i.e., a conventional pressure control method involving PWM control of the inlet valve during pressure increase and time control of the outlet valve during pressure decrease (Brake Manual Fig. 20.12.a).

[0086] Alternatively, based on an inlet valve with tensile resistance in valve terminal variation I, a pressure control method B (multiplex method / PPC method, hereinafter also referred to as "special pressure adjustment mode I") can also be used. The multiplex method / PPC method has significant advantages in ABS control at low road friction values, as shown in Brake Manual 5th Edition, Chapter 20.4 "Integrated Brake System" - Fig. 20.13. This is because the pressure reduction gradient due to pressure reduction through the piston cylinder unit is not limited by the back pressure of the accumulator chamber, and thus a slight reduction in wheel speed at the locked wheel can be achieved. In particular, an inlet valve with tensile resistance in the form of a special solenoid valve is used in an operating mode corresponding to the switching valve shown in Brake Manual 20.12b. Advantageously, as a pressure source and a pressure sink, another pressure supply unit, for example, a second pressure supply unit, is used. The second pressure supply unit may include a piston cylinder unit or a rotary pump. Here, the piston of the piston cylinder unit moves forward during pressure increase and backward during pressure decrease, or the rotary pump changes the rotation direction of the pump motor during pressure increase (p auf ) and pressure decrease (p ab ).

[0087] When using pressure control method B and a piston cylinder unit, the PPC method ("Piston Pressure Control") known in the art can be used, which allows for highly dynamic pressure increase or decrease using sensor signals, current, piston position, and pressure-volume characteristic curves. Furthermore, this approach allows for precise control of the pressure characteristics over time. When a pressure change occurs, the inlet valve is driven to open, and the pressure characteristics are preferably controlled by closed-loop control (closed-loop control via a cascaded control circuit using piston travel distance, piston speed, and electric motor current) or open-loop control (current-proportional pressure open-loop control) solely by volume control via the piston cylinder unit. When increasing pressure, the inlet valve can be driven by time control or by PWM-controlled choke (pressure control method B:p auf / p ab It is also possible to sequentially drive using the multiplex method / PPC method while simultaneously performing the multiplex method / PPC method (p auf :EV PWM ;p ab (1): EV Δt ,p ab (2): AV Δt (Pressure control method). This makes it possible to simultaneously adjust different braking pressures in multiple different wheel brakes with high precision using the driving dynamics system according to the present invention.

[0088] In one embodiment, during operation, it is possible to switch between pressure control method A (standard pressure adjustment mode) and pressure control method B (special pressure adjustment mode I). Preferably, between the pressure control methods, pressure control method A is switched to be used for asphalt (high μ) or sudden changes in friction value (μ split) when controlling ABS pressure, in which case high pressure changes must be achieved simultaneously in multiple wheel brakes. Pressure control method B is preferably used for low friction values, such as on snow or ice (low μ). Preferably, the primary control unit is configured to detect various conditions. In one embodiment, as long as the primary control unit is appropriately configured, the brake circuit of the driving dynamics system can be driven by pressure control method A, and the second brake circuit can be driven by pressure control method B.

[0089] In another embodiment (valve terminal variation II), the valve seat of a special solenoid valve is connected to the wheel brake, thereby allowing the pressure to be choked and reduced by a variable valve opening cross-sectional area. Pressure boosting in this embodiment can be performed simultaneously or sequentially, preferably by piston shifting and by time control instead of PWM drive, based on the multiplex / PPC method, using a second pressure supply unit. In this embodiment, preferably, an open-loop control strategy or a closed-loop control strategy of the first pressure supply unit or primary control unit is adapted, so that when pressure is reduced, the second pressure supply unit is used as an open-loop or closed-loop controllable pressure sink and pressure source. The pressure difference relative to the wheel braking pressure can be detected and set accordingly by determining the piston position. By using such valve terminal variation II, one or more outlet valves can be omitted. For example, a special solenoid valve can be used as an inlet valve that is open when de-energized, and two outlet valves that are closed when de-energized can be used at the front axle. In this case, outlet valves are not required at the rear axle. The corresponding system features high dynamics and low noise generation.

[0090] In valve terminal variation II, the present invention provides a third pressure control method C(p auf :EV ΔT ;p ab (1): EV PWM , p ab (2): AV ΔT A third pressure control method can be used, in which pressure reduction is performed via variable valve cross-section control of the inlet valve. Compared to valve terminal variation I, the pressure can be reduced simultaneously and with low noise through multiple inlet valves. This is particularly advantageous for low-noise closed-loop control operation for electric vehicles. Pressure boosting is performed in one embodiment via pressure control method B (multiplex / PPC pressure control) or pressure control method C.

[0091] This yields embodiments with various pressure control methods, each of which is summarized in the following table.

[0092] [Table 1]

[0093] According to the present invention, pressure can be increased without redundant means (p auf ) and reduced pressure (p ab ) can be performed. For example, pressure boosting can be performed exclusively through the inlet valve (EV) (in the first column, “p auf (See the table row containing "(EV)") and pressure reduction is exclusively due to the outlet valve AV (see the first column "p ab (See the table row containing "(AV)").

[0094] However, preferably, redundant means are provided as shown in the table, in which case, redundant means for pressure boosting preferably include redundant electromagnetic coils and redundant drivers for inlet valves (in the first column, “p auf (See the table row containing "(EV), redundant electromagnetic coil / driver")

[0095] In some embodiments, redundant means are used for pressure reduction, such as an outlet valve (in the first row "pab (See the table column containing "(AV)") or inlet valve (see the first column containing "p ab This can be ensured by performing the procedure via (see the table column containing "EV"). Without such hardware and software redundancy, for example, if the electromagnetic coil of the outlet valve fails, it will not be possible to depressurize through this outlet valve because the valve is closed when de-energized, and therefore depressurization will be prevented. This can result in a persistent lock of the corresponding wheel brake.

[0096] The driving dynamics system according to the present invention generally has the advantage of being able to more easily and efficiently provide individual braking torque intervention and new adjustment strategies for regenerative braking for each wheel. This is because, unlike the prior art, by using special solenoid valves, in at least some embodiments, it is possible to maintain the pressure at a selected wheel brake while changing the braking pressure at other wheel brakes.

[0097] When depressurizing via a special solenoid valve, unlike conventional methods, the pump of the first pressure supply unit must be driven and controlled to return the pressure through the outlet valve. This is particularly true for the embodiments of configurations (C) and (D) described above. However, in the case of ABS operation with low friction values ​​("low μ"), this method is also perfectly feasible with configuration (B). In configuration (E), if one embodiment of the first pressure supply unit is provided with an open-loop or closed-loop controllable pressure sink, for example in the form of a rotary pump, and this open-loop or closed-loop controllable pressure sink can reduce pressure by reversing its rotational direction, a considerable advantage can be obtained.

[0098] The problem mentioned at the beginning can be further solved by a method. In particular, the above problem relates to a method for adjusting the braking pressure in at least one wheel brake of a braking system, comprising the following steps, namely: - A step of determining that the pressure should be reduced from at least one of the wheel brakes, i.e., the target wheel brake, - A step of selecting a decompression mode from a first decompression mode and a second decompression mode, -If the first decompression mode is selected, the steps include opening at least one of the outlet valves associated with the target wheel brake in order to perform decompression, -When a second depressurization mode is selected, the steps include keeping the outflow valve associated with the target wheel brake closed, opening at least one of the inflow valves associated with the target wheel brake, and forming a pressure difference in a (external) preferably second pressure supply unit in order to depressurize from the target wheel brake through the inflow valve. This is resolved by methods including the following.

[0099] Therefore, one aspect of the present invention is that, for optimal pressure reduction, it is possible to select from different modes, particularly depending on the situation. In at least one mode, pressure reduction is performed via a (special) inlet valve. This allows for improved availability (e.g., operation in the event of partial valve failure) on the one hand, and lower pressure oscillations and consequently less noise on the other hand. That is, • Pressure can be generated even if the outlet valve fails (the outlet valve is closed and unpowered when it fails), • The pressure reduction is controllable via an external pressure source, and the pressure gradient and / or pressure gradient characteristics are either closed-loop or open-loop controllable. • Pressure reduction can be performed with low noise via a special valve when valve terminal variation II is selected.

[0100] Within the framework of the present invention, keeping a valve, particularly an outlet valve, in a closed state does not necessarily require that the valve be operated in any way. Rather, the present invention makes it possible to keep a valve that is closed in an unpowered state, often used as an outlet valve, in a closed state by the absence of current application and the absence of any kind of operating signal output.

[0101] Alternatively, the above problem is a method for performing ABS braking in a vehicle, - Determine the required pressure reduction gradient for at least one wheel brake, - The required pressure reduction gradient is used to select a pressure adjustment mode from multiple pressure adjustment modes, in which case the pressure adjustment mode includes at least a first pressure adjustment mode and a second pressure adjustment mode. -When the first pressure adjustment mode is selected, time control is used to reduce the pressure from at least one wheel brake through at least one outlet valve, -When the second pressure adjustment mode is selected, preferably when the outlet valve is closed, the pressure reduction from the wheel brake is performed exclusively via another solenoid valve, where the pressure from the wheel brake is performed in a pressure sink that is open-loop controllable or closed-loop controllable via another valve. It is resolved by methods including those mentioned above.

[0102] In other words, the selection of the mode used for decompression depends on the required pressure gradient. Additionally or alternatively, the amount of fluid to be released or the pressure difference can also be considered in the selection.

[0103] The first pressure adjustment mode may be the standard pressure adjustment mode already described. The second pressure adjustment mode may be special pressure adjustment mode I.

[0104] In one embodiment, the multiple pressure adjustment modes include a third pressure adjustment mode, such as a special pressure adjustment mode II. When the third pressure adjustment mode is selected, pressure reduction from at least one wheel brake can be performed at least in parallel in time via at least one outlet valve associated with one wheel brake and at least one solenoid valve associated with another wheel brake. The other solenoid valve may be a special solenoid valve as described in relation to various embodiments. By utilizing the inlet and outlet valves at least temporarily simultaneously for pressure reduction, the pressure can be reduced quickly and efficiently.

[0105] In one embodiment, when a second pressure adjustment mode is selected, the pressure in the pressure sink is adjusted to a low pressure, particularly <5 bar, preferably <3 bar.

[0106] The problem mentioned at the beginning is similarly solved by a primary control unit having instructions to perform at least one of the methods described above.

[0107] Furthermore, the above-mentioned problems are solved by a vehicle or driving dynamics system equipped with one of the primary control units described above, particularly the last primary control unit described.

[0108] Another advantageous embodiment can be obtained based on each dependent claim.

[0109] The present invention will be described in detail below with reference to the drawings, using several embodiments. The following is shown in the drawings. [Brief explanation of the drawing]

[0110] [Figure 1] This diagram shows a conventional ESP hydraulic circuit. [Figure 2a] This diagram shows the FDS system architecture, which includes a primary control unit, multiple secondary control units for the traction motor, and two brake modules BM1 and BM2. [Figure 2b]This figure shows an exemplary embodiment of a brake module, as shown in Figure 2a, which is equipped with a special solenoid valve as a separation valve. [Figure 2c] This figure shows variations in valve terminals for connecting the special solenoid valve, which acts as a separation valve, in the second brake module, as shown in Figure 2b. [Figure 3a] This is a schematic diagram showing the first brake module BM1, in which the two inlet valves of the brake circuit are equipped with special solenoid valves that have tensile strength (having a 3-channel braking torque modulation function). [Figure 3b] This is a schematic diagram showing a first brake module equipped with a connected second brake module, wherein the first brake module is equipped with special solenoid valves that have tensile strength in the four inlet valves of the two brake circuits (having a 4-channel braking torque modulation function). [Figure 4a] This is a schematic diagram showing a special solenoid valve equipped with a permanent magnet and a return spring. [Figure 4b] Figure 4a is a displacement-force graph showing the forces acting on the valve operating member of a special solenoid valve. [Figure 5a] This is a schematic diagram showing a special solenoid valve equipped with permanent magnets incorporated into the valve armature, where the armature can be operated by electromagnetic fields having different polarities. [Figure 5b] This is a displacement-force graph showing the force acting on the valve operating member of the special solenoid valve shown in Figure 4a, depending on the applied current. [Figure 6] Figure 5a shows an H-bridge used as a driver for a special solenoid valve to form electromagnetic fields with different polarities. [Figure 7a] This is a schematic diagram showing a modified version of the embodiment shown in Figure 3b, without a USV valve (with 4-channel braking torque modulation function). [Figure 7b] This is a schematic diagram showing a modified embodiment of the example shown in Figure 3b, which has no USV valve and is equipped with a check valve as a replacement for the HSV valve (having a 4-channel braking torque modulation function). [Figure 8a]This is a schematic diagram showing a first brake module for two wheel brakes, equipped with a single-piston pump (for reducing pressure to a storage chamber) in which two inlet valves are configured as special solenoid valves. [Figure 8b] This figure schematically shows a modified version of the embodiment shown in Figure 8a, which is equipped with a multi-piston pump (for reducing pressure inside the storage container). [Figure 8c] This is a schematic diagram showing a modified embodiment of the example shown in Figure 8a, in which a rotary pump (for depressurization into the storage container via an outlet valve, and / or depressurization via a special solenoid valve equipped with a rotary pump that is open-loop controlled or closed-loop controlled as a pressure sink) is provided instead of a piston pump. [Figure 9] This is a schematic diagram showing a modified embodiment of the example shown in Figure 7b, which has a single hydraulic terminal for the second brake module. [Figure 10] This is a schematic diagram showing a modified form of the embodiment shown in Figure 9, without the storage chamber. [Figure 11] This is a schematic diagram visualizing the control strategy for the inlet valve. [Figure 12] This is a schematic diagram visualizing the control strategy for the outflow valve. [Figure 13a] Figure 3a shows a schematic diagram illustrating the use of the first brake module in relation to an electrically driven piston cylinder unit as a second brake module, visualizing the reduction in pressure from the two wheel brakes. [Figure 13b] Figure 13a is a schematic diagram illustrating an embodiment that visualizes the pressure reduction within the two wheel brakes. [Figure 14] Figure 3b shows a schematic diagram illustrating the use of the first brake module, which is associated with an electrically driven piston cylinder unit as a second brake module, and visualizes the pressure reduction. [Figure 15] Figure 3b shows a schematic diagram illustrating the use of the first brake module in relation to a centrifugal pump as a second brake module, visualizing the pressure reduction.

[0111] Explanation of the diagram Figure 1 Figure 1 shows the hydraulic circuit diagram of the first brake module BM1 configured as a standard ESP unit. The first brake module BM1 performs the function of the first pressure supply unit. The first brake module BM1, -Four time-controlled outflow valves AV1-AV4, each corresponding to one wheel brake RB1-RB4, -Four PWM-controlled inlet valves EV1-EV4, each corresponding to one wheel brake RB1-RB4, - Four check valves are arranged in parallel to one of the inlet valves EV1 to EV4, and each of them corresponds to one of the wheel brakes RB1 to RB4. This includes the following. Check valves are positioned to be blocked when the pressure is increased in the wheel brakes RB1-RB4 and to be opened according to the pressure conditions when the pressure is reduced. Furthermore, valves HSV1 and HSV2 pump brake fluid via pump P, which is driven and controlled by motor M, when valves USV1 and USV2 are closed, thereby increasing the pressure. Finally, pump P and motor form a Meine 2-piston pump (first pressure generator DV1) with one piston each for one first brake circuit BK1 and one second brake circuit BK2, respectively. The storage chamber Spk allows for the storage of brake fluid via outlet valves AV1-AV4 when the pressure is reduced. The arrows indicate the possible flow directions of brake fluid during pressure increase and reduction.

[0112] The first brake module BM1 shown in Figure 1 provides ESP and ABS functions. The ESP function is well-known and documented in the literature, and requires 12 solenoid valves for its operation. For the ABS function, only 8 solenoid valves are required: inlet valves EV1-EV4 and outlet valves AV1-AV4. The first brake module BM1 has two brake circuits BK1 and BK2, which are connected to a second pressure supply unit via two connection points. In this case, this is... I. Vacuum brake booster using conventional technology, II. Electrical follow-up brake booster and brake pedal, III. Pedal-sensitive simulator and brake booster having a brake pedal, IV. Second pressure generator DV2 equipped with a valve, It may be any of the following.

[0113] The first pressure supply unit in Figure 1a has a pressure sensor p / u positioned to detect the pressure in the brake circuit BK1.

[0114] The following table shows various functions of the latest driving dynamics system.

[0115] [Table 2]

[0116] [Table 3]

[0117] Figure 2a Figure 2a shows the architecture of the driving dynamics system FDS according to the present invention. The driving dynamics system has a first traction motor TM1 and a second traction motor TM2 on the rear axle HA of the vehicle, and a third traction motor TM3 on the front axle VA. The system may have a brake module BM1 and, as an optional means, another brake module, for example, a second electro-hydraulic brake module BM2. The main element of the driving dynamics system is the primary control unit M-ECU-Chassis Domaen, abbreviated as M-ECU, which performs closed-loop control of the braking torque from the traction motors TM1, TM2, TM3 and brake modules BM1, BM2, with the following functions: A) Emergency braking system with simultaneous electronic brake force distribution (EBV), B) Individual regenerative brakes for each axle or each wheel, C) Brake operation via electric motor in the event of brake module failure D) Individual braking torque intervention for each wheel for steering assistance or vehicle stabilization. To undertake for at least one of the following.

[0118] The primary control unit M-ECU transmits target values ​​to various mechanisms, where the target values ​​include, in particular, a target braking torque or a target braking pressure. For specific functions, target signals for pressure open-loop control or pressure closed-loop control, such as a control signal to a solenoid valve and / or a preload to a second brake module BM2, can be set by a second pressure generator DV2 for pressure boosting or depressurizing.

[0119] In one embodiment, the primary control unit M-ECU is the control device M-ECU AD Alternatively, it may have an interface to the domain of autonomous driving and evaluate further information useful for effective and predictive closed-loop control. Such information may include, for example, camera information about the nature of the road (snow, ice, rain) or information about the surrounding environment (distance to occupants and / or other vehicles).

[0120] Figure 2b Figure 2b shows a so-called two-box brake system including a first brake module BM1 and a second brake module BM2. The first brake module BM1 is configured similarly to the first brake module in Figure 1a and has the functional range described above. The second brake module BM2 has a piston cylinder unit (also called a plunger) driven by a spindle drive unit. The piston cylinder unit forms a second pressure generator DV2. Two isolation valves TV1 and TV2 are provided as part of the second brake module BM2, and these isolation valves TV1 and TV2 can isolate the brake circuits BK1 and BK2 from the second pressure generator DV2, thereby enabling the core function, i.e., - Brake booster; - Automatic emergency braking (AEB); -Electronic brake force distribution EBV; - 2-channel ABS function using multiplex / PPC method; It can be executed.

[0121] In one embodiment of the present invention, redundant functions can be provided to satisfy the requirements for autonomous driving in stages 4 and 5.

[0122] The two brake modules BM1 and BM2 are equipped with control devices referred to below as secondary control units S-ECU1, S-ECU2a, and S-ECU2b, and these control devices communicate with each other, preferably with interface functions Int (for example, according to the VDA360 interface definition). 2BM The system has the following features: Based on communication means between the brake modules BM1 and BM2 and the (higher-level) control functions of the primary control unit M-ECU, these components can interact to perform a predetermined function, such as braking, in which the pressure generator of the second brake module performs pressure increase and decrease, and at the same time, valves in the first brake module, such as wheel inlet valves EV1 to EV4 and wheel outlet valves AV1 to AV4, are operated.

[0123] Brake modules BM1 and BM2 are connected to the primary control unit M-ECU via interfaces IntBM1 and IntBM2, respectively, enabling them to perform other functions, such as ABS, ESP, AEB, ACC, and new domain functions, namely torque vectoring (BtTV), braking-induced steering intervention (BtS), and regenerative management for electric traction motors TM1, TM2, and TM3. In this context, brake modules BM1 and BM2 function as slaves, i.e., pure pressure regulators, and can execute set target values, such as pressure torque values ​​or braking torque target values.

[0124] In at least one operating mode, the interface is used by the primary control unit M-ECU to synchronize the operation of (firstly) two brake modules BM1 and BM2, for example, by moving the piston of the second pressure generator DV2 of the second brake module BM2 while simultaneously switching one or more solenoid valves of the first brake module BM1. Providing separate interfaces for each brake module allows for arbitrary replacement of brake modules BM1 and BM2, i.e., brake modules BM1 and BM2 can be purchased from various suppliers. Alternatively, only interfaces IntBM1 or IntBM2, which are communicatively connected to the primary control unit M-ECU, may be provided. In this case, communication with the other unit is performed via a standardized interface Int2BM. In this embodiment, the wheel rotation speed sensors vR1, vR2, vR3, and vR4 are redundantly read by at least two control devices, for example, one of the secondary control units S-ECU1, S-ECU2a, S-ECU2b and the primary control unit M-ECU, thereby enabling the wheel rotation speed signals to be constantly transmitted via the interfaces IntBM1, IntBM2, and Int2BM.

[0125] In the illustrated embodiment, the second brake module BM2 includes a check valve RV. NF (Alternatively, check valve RV) NFIt is hydraulically connected to the storage container VB via a solenoid valve (a solenoid valve may be used instead), and preferably has two 3-phase terminals (2×3) to satisfy the requirements of autonomous driving in stages 4 and 5, where the three phases are driven and controlled by secondary control units S-ECU2a, S-ECU2b, where current sensors i / u and motor angle sensors α / u are provided, these current sensors i / u and motor angle sensors α / u are preferably configured redundantly, and are used for high-precision PPC pressure open-loop control or pressure closed-loop control via piston position or current. The redundant configuration of several components of the second brake module BM2 enhances availability and allows for the formation of a third fallback level, similar to the steer-by-wire configuration of SAE stage 5 (which includes two steering actuators, here comprising 2x3 phase motor terminals and partially redundant electronic circuits). For example, in the event of a pump motor failure or partial motor failure (motor winding, output stage in ECU2a or ECU2b of the second brake module BM2), braking torque formation and control at approximately 50% of the motor torque are still possible. Preferably, a pressure sensor p / u, primarily used for calibration purposes, is provided on the output side of the pressure supply device of the second brake module BM2. Note that if the relationship between BM2 braking torque and current or piston position is formed in other ways, closed-loop or open-loop pressure control can be performed without such a pressure sensor. This also provides further redundancy.

[0126] (Circuit) As separation valves TV1 and TV2, in the embodiment shown in Figure 2a, two special solenoid valves MV2k are used in the second brake module BM2. The special solenoid valves MV2k are particularly tensile and are configured to increase and decrease pressure with a large flow rate Q. Preferably, the pressure change is suitable for highly dynamic conversion of pressure changes for ABS operation using the multiplex / PPC method (i.e., so that the pressure gradient is >1000 bar / s, preferably >2000 bar / s). According to the present invention, the special solenoid valves are designed to have tensile strength according to the system specifications, i.e., according to the maximum braking pressure and maximum volumetric flow rate.

[0127] In one embodiment, a special solenoid valve MV2k having a first soft iron magnetic circuit EM1 and a second magnetic circuit EM2 as shown in Figure 4, or a special solenoid valve MV2k having a magnetic circuit EMI and a permanent magnet PM in the valve armature as shown in Figure 5a, is used. When a special solenoid valve MV2k having a permanent magnet PM embedded in the armature is used, an H-bridge is preferably used for current control, as will be described in detail with reference to Figure 6. In this case, the special solenoid valve MV2k is current-controlled and driven with a variable valve cross-sectional area in both pressure increase and pressure decrease. This enables high-precision pressure control with particularly low noise in pressure increase and pressure decrease. In the latter configuration, magnetic circuits EMI and excitation coil SP1 can be used to generate magnetic forces of different magnitudes in the two directions of motion. Due to the advantageous positioning of the permanent magnet PM, a return force is generated even when no power is supplied, thereby eliminating the need for a return spring RF. However, according to the present invention, in addition to the permanent magnet PM, at least one return spring RF can also be provided, as can be seen, for example, from Figure 4.

[0128] Instead of the valves in Figures 4 and 6, a standard valve having a magnetic circuit EM1 without a permanent magnet can be used as a special solenoid valve; for this, please refer to the prior art in a one-box brake system, i.e., reference numerals 26a and 26b in Figure 1. These valves are designed according to the function to be performed, in particular the ABS function and the pressure difference and pressure change rate of the ABS function. Depending on the function, a stronger magnetic circuit with a stronger armature and / or a larger return spring can be used.

[0129] The first brake module BM1 operates autonomously in standard pressure adjustment mode (pressure control method A), while brake module BM2 operates in pressure control method B. Furthermore, according to the present invention, when ABS operation is performed at extremely low road friction values ​​(low μ, μ split), it is possible to switch between the standard pressure adjustment mode, a special pressure adjustment mode I with pressure reduction via a special solenoid valve, and the use of brake module BM2 as a pressure sink with a pressure of <5 bar, especially a pressure of <3 bar.

[0130] The switching mechanism described here also applies to another embodiment of a brake device with two brake modules in a configuration comprising a storage chamber and brake modules (see Figures 3a, 3b, 7a, and 7b), so it will not be explained separately below.

[0131] Figure 2c Figure 2c shows the advantageous connection configuration of the valve seat VS (e.g., in Figure 5a) and the armature chambers of the separator valves TV1 and TV2 to the brake circuits BK1 and BK2. Here, the armature chamber AR is hydraulically connected to the pressure generator DV2 of the second brake module BM2 (e.g., in Figure 5a), and the valve seat of the special solenoid valve MV2k is connected to the brake circuit. This configuration allows for adjustment of the valve opening cross-sectional area, particularly by PWM control or current control during pressure reduction, thereby enabling low-noise pressure reduction. In this configuration, pressure increase is performed via volumetric metering, which is open-loop or closed-loop controlled using the second brake module BM2, where the separator valves TV1 and TV2 are preferably time-controlled during pressure increase, and pressure increase is performed using the multiplex / PPC method.

[0132] When the special solenoid valve MV2k shown in Figure 5a is used, pressure can be increased by a variable valve cross-sectional area through special current control via an H-bridge (see Figure 6), thus avoiding the dead time of the multiplex / PPC method and enabling simultaneous pressure increase without high demands on the drive device. In this embodiment, the connection direction is not important because bidirectional choking can be performed using the special solenoid valve MV2k shown in Figure 5a. Additionally, the special solenoid valve MV2k can be driven to have tensile strength by appropriate energization, depending on the circumstances.

[0133] Figure 3a (abbreviated) ESP-X 3k,i2Mv,4RB,SK,KP ) Figure 3a (abbreviated) ESP-X 3k,i2Mv,4RB,SK,KP In the first brake module BM1, an embodiment of the present invention is shown in configuration as a three-channel brake system comprising twelve solenoid valves, four wheel brakes RB1-RB4, a storage chamber Spk, and a piston pump, which differs from a standard ESP system in that in the first brake circuit BK1, two inlet valves EV1 and EV2 are configured as special solenoid valves MV2k. The parallel connection of check valves (see RV in Figure 1) can be omitted based on the special tensile strength characteristics of these valves.

[0134] In one embodiment, the special solenoid valve MV2k is provided with redundant solenoid coils MSI and MS2 and a redundant solenoid valve driver, thereby enabling redundant operation, or the solenoid valve driver can be driven and controlled via the primary control unit M-ECU. In the illustrated embodiment, the first brake circuit BK1 corresponds to the vehicle's front axle brake circuit in II-Braking Force Distribution. That is, the wheel brakes RBI and RB2 are the wheel brakes of the vehicle's front axle VA.

[0135] In an alternative embodiment, an X-brake circuit distribution may be selected. In the minimum configuration, in this embodiment, the inlet valves EV1 and EV2 associated with the wheel brakes RB1 and RB2 of the front axle VA can be configured as special solenoid valves MK2k. Such a modification of the standard brake system can achieve a significant improvement because a three-circuit brake system is introduced from a two-circuit brake system, where redundancy in pressure boosting and depressurization is obtained for the two wheel brakes (see wheel brakes RBI and RB2 in Figure 3a). Unlike the prior art, if one of the first wheel brakes RB1 or the second wheel brakes RB2, for example wheel brake RB1, fails, each wheel brake circuit can be isolated by closing the inlet valve EVI associated with the defective wheel brake RB1. This allows the control operation of the remaining three wheel brake circuits, including wheel brakes RB2-RB4, to continue. Additionally, if one of the solenoid coils of the outlet valves AV1 and AV2 fails, the pressure can be redundantly reduced through the respective inlet valves EV1 and EV2. This assumes that each driving dynamics system has a controllable pressure sink, for example, by providing a corresponding second brake module BM2. This approach of the present invention can achieve a significant improvement in achievable deceleration compared to the prior art, because in the event of failure, either (a) the wheel brakes RB1, RB2 provided on the front axle VA and the two wheel brakes RB3, RB4 provided on the rear axle HA, or (b) the two wheel brakes RB1, RB2 provided on the front axle VA will be used for braking.

[0136] In one embodiment, the above interface between brake modules by VDA360 is extended to allow external operation of inlet valves EV1-EV4 in addition to the interface described in German Patent Application Publication No. 102012211278. This enables selective braking torque intervention for steering (BtS) by the remaining three brake circuits, including yaw rate control (ESP), torque vectoring via individual wheel braking torque intervention (BtTV), and in the event of a wheel circuit failure. This approach according to the present invention further has the advantage that all the functions described in the table above can be retained, particularly within the first brake module BM1, without major software changes. The software component responsible for pressure boosting must be modified to provide additional functionality for three-circuit closed-loop control in the event of a wheel circuit failure. Furthermore, a control strategy that enables pressure adjustment for the primary control unit M-ECU can be implemented at minimal development cost because the pressure can be maintained in the two wheel brakes RB1-RB4 by special solenoid valves. Thus, the specially configured inlet valves EV1-EV4 allow for individual pressure increases and decreases for each wheel using the second brake module BM2. When individual brake torque closed-loop control or brake torque open-loop control is performed for each wheel, there is no need to depressurize via the outlet valves AV1-AV4 (all separation valves TV1-TV4 converted by special solenoid valves as shown in Figure 3b) or outlet valves AV1,AV2 (converted as shown in Figure 3a), and the costly repressurization of brake fluid using pump P can be omitted. Eliminating the need for such return requests eliminates the need for complex pressure vibration compensation by the second brake module BM2 during return pressurization by the first brake module BM1, which has a favorable effect on noise and wear.

[0137] International Publication No. 2018234387 (pp. 23-25) describes a fade strategy for a two-box brake system that can be used for braking torque open-loop control and braking torque closed-loop control during torque vectoring or steering intervention. By using the special solenoid valve MV2k, the fade strategy or individual braking torque intervention for each wheel can be implemented with significantly greater ease. Further flexibility is gained because the pressure supply unit of the second brake module BM2 can maintain pressure in the wheel brakes RB1-RB4 even when a different preload is adjusted for the other wheel brakes.

[0138] In one embodiment, the first brake module BM1 can be extended by two check valves RV1 and RV2, which are part of the connection between the pump P of the brake circuits BK1 and BK2 and the storage container VB (see the dashed connection in Figure 3a). This allows for significantly faster suction by the pump compared to the conventional technology, which is more rapid than the suction process via a separate hydraulic resistance based on the combination of valves HSV1 and HSV2 and the second brake module BM2.

[0139] Figure 3b (abbreviated as ESP-X) 4k,MV,4RB,SK,KP ) Figure 3b (abbreviated as ESP-X) 4k,MV,4RB,SK,KPIn this embodiment, the first brake module BM1 according to the present invention is shown as a four-channel brake system comprising 12 solenoid valves, four wheel brakes RB1-RB4, a storage chamber Spk, and a piston pump KP, which differs from the standard ESP in that all inlet valves EV1-EV4 and their check valves RV1-RV4 (see Figure 1a) in the two brake circuits BK1 and BK2 are replaced by one special solenoid valve MV2k each. This embodiment provides a four-circuit brake system, which provides further flexibility for individual braking torque control for each wheel and a simple pressure interface to the primary control unit M-ECU. By providing the four-circuit brake system in the first brake module BM1, the brake circuit distribution in the second brake module BM2 can be omitted. For example, the second brake module may include a simple master brake cylinder (HZ) having a single piston (a so-called single master brake cylinder SHZ) and a pressure chamber, as described in International Publication No. 2020165294, where the master brake cylinder is preferably configured with redundant seals, and the SHZ must be connected to only one brake circuit, for example, the brake circuit of the front axle brake circuit. If the wheel circuit in the first brake module fails, even if the pump P subsequently fails, it is sufficient to ensure that only the defective wheel brake circuit is isolated. According to the present invention, this can be done by each inlet valve EV1 to EV4, which can be driven and controlled internally and externally. For this purpose, the special solenoid valve MV2k is provided with redundant coils and redundant solenoid valve drivers.

[0140] Figure 4a Figure 4a shows a first advantageous embodiment of a solenoid valve MV2k that is tensile-resistant and bidirectional, and is open when unenergized. According to the present invention, the term “bidirectional” can be understood to mean that pressure increase and pressure decrease occur through the MV2k valve. The special solenoid valve MV2k is particularly suitable for two flow directions Q, especially 100 cm 3 / s~120cm 3 It operates reliably with high flow rates of / s and even with pressure differences between terminals, such as 160 bar to 220 bar.

[0141] The special solenoid valve MV2k has a typical solenoid valve structure, comprising an electromagnetic circuit EM1, an armature 6, and a valve operating member 7, where the valve operating member 7 includes a valve tappet 7a that closes the valve seat VS. Furthermore, a return spring RF is provided, which has linear force characteristics and acts on the valve operating member 7. The return spring applies a preload to the special solenoid valve MV2k at its starting position (the position shown in Figure 4a).

[0142] In particular, with respect to large pressure changes and the aforementioned range of flow rates, the special solenoid valve MV2k is guaranteed not to automatically close due to the action of hydrodynamic forces. This is important when high pressure is present in the armature chamber AR and low pressure is present at the hydraulic connection acting on the valve seat VS. In a hydrodynamic flow, force F hyd This force F occurs, hyd This applies a force to the valve tappet so that it moves in the direction of the valve seat VS. The return spring RF acts against the hydrodynamic force, but in extreme cases, it is not sufficient to actively prevent tension under the action of the hydrodynamic force.

[0143] The magnetic circuit EM1 (see Figure 4b) exerts a current-dependent and position-dependent magnetic force F through a stroke s, causing the armature to move towards the stopper and the valve tappet 7a towards the valve seat VS. EMI = f(isp) is generated. The magnetic force characteristics are nonlinear, and as the small air gap S (see Figure 4) increases, F in particular occurs. EMI =(s max -s) n The current i increases gradually with increasing stroke s, or with decreasing air gap S between armature 6 and stopper (smax-s), according to a polynomial n=1,4-2. SPIncreasing the value can increase the magnetic force, but this is limited by the saturation of the magnetic circuit. However, the magnetic force can only act in the direction of the valve seat VS, and therefore, if the flow Q originates from the armature chamber, the hydrodynamic force F hyd It does not generate a reaction force. When the valve is closed and energized, the valve can remain closed against the pressure acting on the valve seat. If the flow originating from the valve seat VS can generate a reaction force, operation with a variable opening cross-sectional area is also possible; that is, the special solenoid valve MV2k can be driven in the same way as a proportional valve with a variable valve opening cross-sectional area. In technical terms, this type of control is simply called PMW control.

[0144] In order to construct a special solenoid valve MV2k with tensile resistance, in the first modified form, the permanent magnet PM is subjected to a return force F generated by the return spring RF. RF It is provided as a passive force-applying device for amplifying the magnetic force F. The permanent magnet circuit includes a permanent magnet PM and a magnetic pole plate 10. The permanent magnet is incorporated into an additional armature 6a, which is connected to the armature 6 by a friction connection. The magnetic poles are oriented parallel to the longitudinal direction of the special solenoid valve MV2k, so that the magnetic force F of the permanent magnet PM is present. PM The return force F RF It acts additively on and the maximum force is F ges =F PM +F RF This is the result.

[0145] The magnetic force FPM is characterized by being large when the valve is open and decreasing as the stroke s increases. max In this case, it is still large enough to handle the return of a normal armature. With appropriate design, the magnetic force FEM1 generated through the coil SP2 and the primary magnetic circuit EMI is large enough to overcome the reaction force of the permanent magnet or return spring, and considering that this can be achieved by forming an appropriate characteristic curve of the EM magnetic circuit, the return spring 13 can be replaced.

[0146] Supplementary or alternative, an additional return force to the first electromagnetic circuit EM1 can also be formed by the second electromagnetic circuit EM2. The second electromagnetic circuit EM2 is generated by the current in the second coil SP2, and the electromagnetic field extends through an additional electric machine 6a, preferably made of a ferromagnetic material. Therefore, in this modified form as well, a hydrodynamic force F similar to the return force FRF of the return spring RF is formed. hyd A force is formed that acts in opposition to this. In this modified form as well, the armature 6 is mechanically coupled to the additional armature 6a.

[0147] As one embodiment, if the force application device is appropriately sized, the return spring RF can be omitted.

[0148] The essential characteristic of the special solenoid valve MV2k is that it operates at full force F throughout the entire stroke. Ges The force extends substantially linearly. Preferably, the force increases at the starting position or when moving away from the starting position. A characteristic force distribution over the stroke s is shown in Figure 4b. This figure also shows that the special solenoid valve MV2k according to the present invention exhibits a force distribution (see FGes) that is clearly different from that of valves conventionally used in this region (see return force FRF).

[0149] Figure 5a Figure 5a shows a second advantageous embodiment of a special solenoid valve MV2k that is tensile-resistant, bidirectionally effective, and open in the unenergized state. The special solenoid valve MV2k is suitable for the aforementioned use in the first brake module BM1 (as inlet valves EV1-EV4) and the second brake module BM2 (as separator valves TV1, TV2).

[0150] The special solenoid valve MV2k has a typical structure for a solenoid valve having an electromagnetic circuit EMI. The special solenoid valve MV2k has an armature 6, a valve actuating member 7 having a valve tappet 7a, and a valve seat VS. In this embodiment, an annular permanent magnet PM covered with a soft magnetic element is incorporated into the armature 6 (magnetic flux conductor). The magnetic poles of the permanent magnet PM are oriented transversely with respect to the longitudinal direction of the special solenoid valve MV2k. Alternatively, a plurality of permanent magnets PM oriented radially can be provided. The electromagnetic field EMI is formed by a coil SP1a extending in a circular orbit within a predetermined portion of the housing of the special solenoid valve MV2k by an excitation current. The electromagnetic circuit EMI extends across the left leg of the housing, conducts through the magnetic flux conductor in the armature across a first air gap, and closes across a second air gap in the right leg, in which case the two legs are located in the housing and are ferromagnetic and conductive. Since the left and right legs are separated from each other by a large air gap, the electromagnetic field does not directly flow from the left leg to the right leg. When energized, magnetic poles are formed in each leg, and these magnetic poles selectively attract or repel the permanent magnet PM in the direction of the magnetic flux by the excitation coil SP1a, depending on the direction of the current.

[0151] In this embodiment, the remaining armature 6 is manufactured from a non-electromagnetically conductive material. For example, the armature 6 can preferably be manufactured from a low-cost plastic component, including the valve actuation member 7. In the starting position, the armature 6 is positioned such that the flow conductor is closer to the left leg than to the right leg. As a result, the armature 6 is subjected to a force that opens the valve, equivalent to the force acting of the magnetic force FPM and / or return force FRF in Figure 4a. This makes it possible to omit the return spring RF. Furthermore, since the configuration of the magnetic circuit is easily reproducible, the return force is loaded via the flow conductor, for example, with a small tolerance to the return spring RF.

[0152] In the embodiment shown in Figure 5a, the excitation coil SPa is driven and controlled via an H-bridge (see Figure 6) with four power semiconductors. This allows the direction of the magnetic flux to be changed by reversing the direction of the current. As a result, the electromagnetic field EMI can be increased or decreased in force acting on the permanent magnet PM. The electromagnetic field can also be reversed so that a special solenoid valve MV2k is closed. Consequently, the armature 6 can be moved to the right or left in the plane of the figure via current open-loop control or current closed-loop control.

[0153] The embodiment described has the advantage that the valve is formed very easily. The H-bridge includes four power semiconductors, as can be seen in Figure 6, and the magnetic flux direction can be determined according to the circuit of the power semiconductors. When power semiconductors S2 and S3 are connected, currents i1,i2 generate a first magnetic flux direction, resulting in the formation of a north pole in the left leg and a south pole in the right leg, causing the armature 6 to be magnetically repelled, i.e., the valve to close. When power semiconductors S1 and S4 are connected, current i3 generates a second magnetic flux direction, resulting in the formation of a south pole in the left leg, causing the armature to be attracted, i.e., the valve to open or be held in the open position. The drive control according to the present invention via the H-bridge can even amplify the return force of the permanent magnet PM, thereby giving the valve extreme tensile resistance and enabling it to open very quickly. Rapid opening has the advantage of reducing the dead time during depressurization due to the valve opening process, which is typically 2 ms, to less than 1 ms. This enables rapid depressurization without time loss, which is advantageous for ABS control quality and braking distance. Furthermore, the cross-sectional area of ​​the special solenoid valve MV2k can be controlled with extreme precision during pressure increase, and a large valve opening cross-sectional area, which has the advantage of reduced choke action due to a large valve stroke, can be easily achieved with this approach. Drive control according to the present invention via an H-bridge allows the special solenoid valve MV2k to be driven with a variable valve cross-sectional area both during pressure increase and pressure decrease. This enables highly accurate pressure control, especially with low noise, both during pressure increase and pressure decrease.

[0154] In one embodiment, the special solenoid valve MV2k is provided with a large cross-section, which significantly reduces the choking effect during pressure increase. This shortens the time required to achieve the stop pressure.

[0155] The special solenoid valve MV2k described here can eliminate multiple outlet valves AV1 to AV4, and in particular, it provides a means to eliminate two outlet valves in the rear axle HA wheel brakes RB3 and RB4. This is because two-channel multiplex operation can be performed very easily with such a valve.

[0156] Figure 5b Figure 5b shows a graph of the magnetic force FEM1 acting on the armature 6 (see VK for the return force and RC for the return force) over distance s. In this case, the dashed line, limit smax, is the maximum distance over which the valve tappet 7a closes the special solenoid valve MV2k. When there is no energization to the special solenoid valve MV2k (i=0), a relatively high return force is generated at the starting position (s=0) and decreases over distance s. However, a return force still acts at the closed position (s=smax; the valve is closed), preventing undesirable valve pull-out. When energization has a negative sign (see i=i3), a significantly strong return force is generated over the entire distance s.

[0157] When the current is weak with a positive sign (i=i3), a return force is generated only near the initial position. After overcoming this return force, a pre-adjustment force acts to forcibly move the valve tappet to the closed position. When the current is strong with a positive sign (i=i3), the pre-adjustment force acts over the entire distance s, thereby enabling the special solenoid valve MV2k to close in a controlled manner.

[0158] Figure 7a (abbreviated as ESP-X) 4k,10MV,4RB,SK,KP ) Figure 7a (abbreviated as ESP-X) 4k,10MV,4RB,SK,KPFigure 5b shows another embodiment of the first brake module BM1, in which valves USV1 and USV2 are omitted without causing functional limitations. The brake module is a 4-circuit type and has 10 solenoid valves, 4 wheel brakes and 2 storage chambers Spk. This assumes that the first brake module BM1 is driven together with two separate brake circuits BK1 and BK2, and that power is supplied to the two separate brake circuits BK1 and BK2, and that it has separator valves TV1 and TV2 in the form of special solenoid valves MV2k (as can be seen, for example, from Figure 5b). In this case, separator valves TV1 and TV2 take over the functions of valves USV1 and USV2, in particular ESP intervention. In order to implement the above solution, another interface is required between brake modules BM1 and BM2. This approach has the advantage of reducing choke resistance between the pressure generator DV2 of the second brake module BM2 and the wheel brakes RB1-RB4, which makes the system more responsive, and this is positively evident, for example, during emergency braking.

[0159] Figure 7b (abbreviation) ESP-X 4k,8MV,4RB,SK,KP ) Figure 7b (abbreviation) ESP-X 4k,8MV,4RB,SK,KP The diagram shows a first brake module BM1 with valves USV1, USV2 and valves HSV1, HSV2 omitted. The brake module is a four-circuit type and has eight solenoid valves, four wheel brakes RB1-RB4, two storage chambers Spk, and one piston pump KP. Two check valves RV1 and RV2 are provided to perform the functions of valves HSV1 and HSV2, and these two check valves RV1 and RV2 form a connection to the storage container VB. This leads to further cost reductions without functional limitations and without limitations on the range of function.

[0160] Figure 8a (abbreviated) ESP-X 2k,4MV,2RB,SK,KP ) Figure 8a (abbreviated) ESP-X 2k,4MV,2RB,SK,KPFigure 7b shows an embodiment that is a modified version of the embodiment shown in Figure 7b. This embodiment requires only four valves (two inlet valves and two outlet valves). The first brake module can be used for motorcycles or for axles of vehicles with multiple axles. The first brake module has terminals for exactly two wheel brakes RBI and RB2, where each wheel circuit can be separated separately via special solenoid valves MV2k used as separation valves TV1 and TV2.

[0161] In the event of a failure of the wheel brakes RBI and RB2, the remaining wheel brake circuits remain operational and can increase or decrease braking torque. The first brake module BM1 is preferably also provided with an interface IntBM1 to the primary control unit M-ECU, which allows for the direct setting of target settings for individual braking torque intervention for each wheel via the primary control unit M-ECU. The first brake module BM1 operates autonomously in a standard pressure adjustment mode (pressure control method A), and pressure control method B can also be used with an additional pressure supply device DV2. At terminals A1 and A2, the brake module BM1 can be selectively connected to terminal A1 by a separately configured pressure generator DV2 or a second brake module BM2 via hydraulic connection, or to terminal A1 by SHZ. Similarly, as described in Figure 2b, it is possible to switch between the standard pressure adjustment mode and a special pressure adjustment mode I in ABS operation.

[0162] Figure 8b (abbreviated) ESP-X 2k,4MV,2RB,VB,MKP ) Figure 8b (abbreviated) ESP-X 2k,4MV,2RB,VB,MKPAnother embodiment of the first brake module BM1 for two wheel brakes RB1, RB2 is shown, where the pressure generator is a pump with multiple pistons. Pressure reduction is performed directly into the storage container VB via outlet valves AV1, AV2. This has the control technical advantage that control can be greatly improved at low pressures, especially when controlling on snow and ice, because the back pressure in the storage chamber Spk does not limit the pressure gradient when pressure is reduced. In this embodiment, special pressure adjustment mode I is not required.

[0163] The first brake module BM1 is preferably also provided with an interface IntBM1 to the primary control unit M-ECU, which allows for direct setting of VMC targets for individual braking torque intervention for each wheel via the primary control unit M-ECU. The first braking pressure module BM1 functions autonomously by pressure control method A, and pressure control method B can also be realized using a further pressure generator DV2.

[0164] Figure 8c (abbreviated) ESP-X 2k.4MV,2RB,VB,RP ) Figure 8c (abbreviated) ESP-X 2k.4MV,2RB,VB,RP Figure 8a shows an embodiment similar to that of the first brake module BM1 for two wheel brakes. A rotary pump RP is provided as a pressure generator DV1, which can increase the pressure and decrease it by reversing the direction of rotation. Special solenoid valves MV2k, arranged as inlet valves EV1 and EV2 and connected to wheel brakes RBI and RB2, are equipped with redundant excitation coils and redundant drivers. In general, corresponding redundant equipment according to the present invention is possible in all embodiments.

[0165] Two outlet valves AV1 and AV2, each associated with a single wheel brake RB1 and RB2, are hydraulically connected to a storage container VB for effective pressure reduction. This embodiment is highly advantageous in that it provides multiple degrees of freedom for pressure reduction that can be used for improved availability in the event of partial failure or for improved closed-loop control and pressure controllability. Here, pressure reduction can be performed entirely autonomously via the outlet valves AV1 and AV2 (from the perspective of the first brake module BM1). Pressure boosting and depressurization can also be performed separately or using an external pressure generator DV2 provided as part of the second brake module BM2. Therefore, this embodiment is particularly suitable for use as a low-cost, centrally controlled axle module.

[0166] Generally, the rotary pump RP can be used additionally or independently as a first pressure generator DV1 or a second pressure generator DV2 in all the embodiments described. When used as a first pressure generator DV1 within a first brake module BM1, the check valve RV1 between the pump and the storage container VB (see, for example, Figure 3b) can be omitted. The advantage of depressurization via the rotary pump RP is that the depressurization gradient due to the back pressure in the storage chamber Spk is not limited, and it can be used to improve ABS control performance at low pressures without the need for an external pressure generator DV2.

[0167] The first brake module BM1 shown in Figure 3b preferably includes an interface Int to the primary control unit M-ECU. BM1 A system is also provided, which allows for the direct setting of VMC targets for individual braking torque intervention for each wheel via the primary control unit M-ECU. The first brake module BM1 operates autonomously using pressure control method A or special pressure adjustment mode II (where the rotary pump acts as a pressure sink). Pressure control method B (special pressure adjustment mode I) can also be implemented using an additional pressure generator DV2.

[0168] Figure 9 Figure 9 shows an embodiment similar to the embodiment in Figure 8a. In this embodiment, a (single) hydraulic terminal is provided for the second brake module BM2. By using (all) special solenoid valves MV2k in the four wheel brakes RB1 to RB4, the advantage of a four-circuit system is taken advantage of, which eliminates the need to separate the brake circuits.

[0169] The embodiment also preferably includes an interface Int-BM1 (not shown) to a central control unit, preferably in the form of a primary control unit M-ECU, which allows for the external setting of target settings for individual braking torque intervention for each wheel. The first brake module BM1 described herein operates autonomously by pressure control method A and is extendable for pressure control method B (special pressure adjustment mode I) by a second brake module BM2.

[0170] Figure 10 Figure 10 shows a modified embodiment of the embodiment shown in Figure 9 in another example. This embodiment does not have a storage chamber Spk. For pressure reduction, the wheel brakes RB1 to RB4 are hydraulically connected to the storage container VB via outlet valves AV1 to AV4. A single hydraulic terminal is provided for connecting the second brake module BM2. The hydraulic structure is similar to the embodiment shown in Figures 8b and 8c. The first brake module BM1 is designed for four wheel brakes. This embodiment is suitable as a hydraulic actuator driven and controlled via a central computer, such as a primary control unit M-ECU.

[0171] The first brake module BM1 has an optional interface Int to the primary control unit as an optional means. BM1 It has (not shown) which allows for the external setting of target settings for individual braking torque intervention for each wheel. This functions autonomously through pressure control method A and pressure control method B.

[0172] Figure 11 Figure 11 illustrates a first inlet valve EVI that can be used in some or all of the embodiments described. The inlet valve EVI is configured as a special solenoid valve MV2k and has redundant coils, each of which is energized via a driver. The first driver (left) is electrically connected to the secondary control unit S-ECU1 of the first brake module BM1 in which each inlet valve is used. The second driver (right) is connected to two interfaces Int2BM and IntBM1, so that the second driver can be driven and controlled by at least one of the secondary control units S-ECU2a and the primary control unit M-ECU of the second brake module BM2. In one embodiment, the secondary control unit S-ECU1 implements pulse width modulation, i.e., PWM control with voltage clock control. A simple switch is sufficient for this. Control by the primary control unit M-ECU or control by the second brake module BM2 is preferably performed using current control i=f(t). For this purpose, the aforementioned H-bridge can be used. The H-bridge allows for control of the temporal flow characteristics, providing greater flexibility in both design and pressure reduction, particularly with regard to valve cross-sectional area control using variable cross-sectional area. Therefore, pressure can be increased or decreased with low noise. Depending on the embodiment, the H-bridge can be used as a first or second driver. Alternatively, both drivers can also be operated via PWM control.

[0173] Figure 12 Figure 12 shows an outlet valve AVI that can be used in one or all of the embodiments described. The outlet valve AVI has redundant coils, each of which is energized via a driver. The first driver (left) is electrically connected to the secondary control unit S-ECU1 of the first brake module BM1 in which each outlet valve AVI is used. The second driver (right) is connected to two interfaces Int2BM and IntBM1, so that the second driver can be controlled by at least one of the secondary control unit S-ECU2a and the primary control unit M-ECU of the second brake module BM2. The outlet valve AVI is preferably driven in a time control where the opening time is controlled via a voltage U=f(t).

[0174] Figures 13a and 13b Figures 13a and 13b illustrate the functional operation of brake modules BM1 and BM2 in Figure 3a, showing pressure increase (Figure 13a) and pressure decrease (Figure 13b) via the second brake module BM2. Each volume flow is shown schematically. In the upper right corner, there is a graph of pressure against time (t), visualizing the pressure characteristics within the wheel brakes RB1 and RB2.

[0175] In the embodiment shown in Figure 13a, the pressure increase occurs with a delay time Δt mux The process is carried out sequentially according to pressure control method B (MUX) using the multiplex method / PPC method, or pressure control method A (EV PWM This is done using a method in which the pressure increase is performed simultaneously via preload control in multiple wheel brakes RB1, RB2. In the latter method, preferably one valve, e.g., inlet valve EV1, is opened and the other valve, e.g., second inlet valve EV2, is driven by PWM control. Alternatively, the two inlet valves EV1 and EV2 can be driven with different PWM frequencies or current profiles for different valve opening cross-sectional areas to adjust different pressures with the preload given in the wheel brakes RB1 and RB2.

[0176] Figure 13b illustrates the depressurization in wheel brakes RB1 and RB2. The depressurization is performed according to pressure control method B(MUX) in the multiplex / PPC method, within a closed hydraulic circuit, with a delay time Δt mux This is performed sequentially via outlet valves AV1 and AV2, either through a special solenoid valve MV2k or through pressure control method A (standard pressure adjustment mode) having an open hydraulic circuit. Therefore, the pressure can be reduced from wheel brake RB1 in the multiplex / PPC method, and in parallel, the pressure in wheel brake RB2 can be increased via the outlet valve. If rapid pressure reduction is urgently required, the pressure can also be reduced in parallel via the outlet valve and special solenoid valve using a special pressure adjustment mode II (not shown). If the outlet valve fails, the system can switch to the multiplex / PPC method using pressure control method A in the wheel brake. Due to the substitutability and degrees of freedom, it is possible to simulate extremely good control performance for all critical driving conditions, or additionally, redundant 4-channel operation is possible.

[0177] Figure 14 Figure 14 shows the pressure reduction in the configuration of brake modules BM1 and BM2, as explained based on Figure 3b. Volumetric flow is shown schematically. In the upper right corner, there is a pressure graph with respect to time (t), visualizing the pressure characteristics within wheel brakes RB1, RB2, RB3, and RB4.

[0178] According to the control strategy visualized here, depressurization is performed after a delay time Δt following pressure control method B using the multiplex / PPC method. mux This can be done by or via pressure control method A. In the MUX method, via the piston cylinder unit, a target pressure lower than the pressure in the wheel brakes RB1~RB4 is adjusted. Simultaneous depressurization into the storage chamber without delay time via outlet valves AV1~AV4, with a delay time Δt muxThis can be avoided. Therefore, it is not necessary to predict the limitations in critical driving conditions due to the control. In addition, the first brake module BM1 can be optimized in terms of noise because a large pressure gradient is controlled by the MUX method, and it does not have vibrations that generate noise, and a small pressure gradient is realized by the pressure control method A.

[0179] Figure 15 Figure 15 shows a solution according to the present invention with two pressure supply units in the simplest and lowest cost configuration. The brake module BM1 has only eight solenoid valves, as in Figure 10, and in this case all wheel inlet valves are configured to have special solenoid valves, i.e., a brake module BM1 with four wheel brake circuits is provided here. As the second pressure supply unit, an electric motor-driven rotary pump is used instead of an electric motor-driven piston cylinder unit. Based on the embodiment with four wheel brake circuits, only a hydraulic connection to the brake module BM1 is required. The brake module BM1 functions autonomously, but is preferably supported by a third brake module BM3 in normal control.

[0180] Pressure reduction is performed in the standard pressure regulation mode via the outlet valve into the storage container, and simultaneously or alternatively via a rotary pump. Depending on the corresponding rotation direction of the rotary pump, the rotary pump acts as a pressure sink during pressure reduction. In addition to high safety against errors, this embodiment provides numerous degrees of freedom, and in particular, also provides means for switching from the standard pressure regulation mode (pressure boosting via the inlet valve and pressure reduction via time control of the outlet valve) to special pressure regulation mode I and / or special pressure regulation mode II. If the first brake module BM1 fails, the rotary pump takes over the pressure boosting function, and at the same time, the wheel pressure control valve is driven and controlled via the primary control unit M-ECU or another secondary control unit S-ECU2a, S-ECU2b via the communication interface (Int2BM, IntBM1) shown in Figures 11 and 12.

[0181] In the above description, the special solenoid valve is described as a special solenoid valve equipped with a force-applying device, where the force-applying device comprises (primarily) a permanent magnet and / or a second excitation coil and is arranged to form at least one holding force acting on the valve actuator or valve tappet. In at least some of the multiple embodiments and examples described, the special solenoid valve may be a solenoid valve having arbitrary tensile strength. This can therefore be achieved by providing at least one choke that controls the tensile strength so that the volume flow is so small that it does not lead to valve closure.

[0182] Generally, the pull-in action can be limited by limiting the pressure difference in the closed-loop control of the pressure supply unit, or preferably by a choke (not shown). The choke is preferably mounted in front of the armature terminal of the valve terminal in the hydraulic pipeline.

[0183] In some embodiments of the special solenoid valve, the return spring RF can be omitted.

[0184] Furthermore, in at least one of the embodiments described, the driving dynamics system may be configured to allow for the automatic application of core functions in development, particularly through the primary control unit M-ECU, with high computing power. In at least one of the embodiments described above, assistance can be provided through a learning algorithm or artificial intelligence (AI) while the vehicle is in motion. When AI is used, the primary control unit M-ECU can take over the tasks of the application engineer, which is not possible with conventional microcontrollers (i.e., one of the closed-loop or open-loop control units of a brake system based on extremely limited capabilities and limited storage capacity). Thus, the central computer records and evaluates measurement data while the vehicle is in motion to apply various functions, particularly safety-critical functions such as ABS, ESP, and AEB, while the vehicle is in motion or when the vehicle is stationary and therefore adaptation is not time-critical. Hence, adaptation is performed when the vehicle is stopped, especially after the vehicle has been in motion. Here, a preferred embodiment as a closed hydraulic system, primarily performing pressure increase and decrease via bidirectional valves using a pressure supply unit, offers significant advantages. This is because nonlinear relationships can be mapped by appropriate sensors via characteristic maps (e.g., pressure-volume characteristic curves, the relationship between motor current and braking pressure, the relationship between braking pressure and deceleration when the wheel brake is heated) and adapted during operation to detect environmental influences (e.g., air in the system, heating of the wheel brake). Once nonlinear relationships are mapped to mathematical functions or characteristic maps, automatic application of the electrohydraulic brake system is also possible. When the Al approach is consistently applied in hydraulic brake systems (EHCs), the advantages of easily closed-loop or open-loop controllable electromechanical brakes (EMBs) diminish, and the advantage of lower manufacturing costs for hydraulic brake systems becomes even more effective because the disadvantages in application costs are largely eliminated. [Explanation of Symbols]

[0185] M-ECU Primary control unit, central computer R1~R4 Wheels vR1~vR4 Wheel speed sensors RB1~RB4 Wheel brakes BK1,BK2 Brake circuits A1,A2 Terminals BM1 First brake module BM1BE Structural unit of the first brake module DV1 Pressure generator M Motor P Pump unit Spk Accumulation chamber S-ECU1 Control device for the first brake module RP Rotary pump KP Piston pump MKP Multi-piston pump BM2 Second brake module BM2BE Structural unit of the second brake module DV2 Pressure generator S-ECU2a Control device for the second brake module S-ECU2b Control device for the second brake module TV1,TV2 Isolation valves BM3 Another brake module RV,RV1,RV2 Check valves AV1,AV2,AV3,AV4 Outflow valves EV1,EV2,EV3,EV4 Inflow valves HSV1,HSV2,USV1,USV2 Valves of the ESP unit MV2k Special solenoid valve for pressure increase and decrease TM1 First electric traction motor for driving the vehicle axle or wheels TM2 Second electric traction motor for driving the vehicle axle or wheels TM3 Third electric traction motor for driving the vehicle axle or wheels VB Storage container VA Front Axle HA Rear Axle Return Force by FRF Spring FPM Magnetic Force FEM1, FEM2 Magnetic Forces PM Permanent Magnet EM1, EM2 Magnetic Circuits RF Return Spring SP1, SP1a, SP1b, SP2 Excitation Coils 6 Armature 6a Additional Armature 7 Valve Operating Member 7a Valve Tappet 10 Pole Plate 13 Return Spring VS Valve Seat AR Armature Chamber MS1, MS2 Magnetic Coils S Air Gap S1~S4 Power Semiconductors

Claims

1. A driving dynamics system for a vehicle equipped with wheels (R1 to R4), A primary control unit (M-ECU) that detects and / or generates steering commands and braking commands, At least two hydraulically operated wheel brakes (RB1 to RB4) are associated with one wheel each (R1 to R4), A traction motor comprising a traction motor control unit, wherein at least one electric traction motor (TM1, TM2) is arranged to drive at least one of the wheels (R1 to R4), wherein, The primary control unit is communicated to the traction motor control unit in order to control the traction motors (TM1, TM2) in order to execute steering commands and braking commands. At least one electric traction motor, At least one (first) electrohydraulic pressure supply unit (BM1), At least one electric motor pump unit, At least two terminals for connecting the aforementioned wheel brakes (RB1 to RB4), Electrically operated wheel brake pressure regulating valve or brake pressure regulating valve (AV1 to AV4, EV1 to EV4), and First secondary control unit (S-ECU1) A (first) electrohydraulic pressure supply unit (BM1) comprising: Equipped with, At least one of the hydraulically operated wheel brakes (RB1 to RB4) is associated with a braking pressure regulating valve and outlet valve (AV1 to AV4) in the form of a special solenoid valve (MV2k) that has particular tensile strength. In the driving dynamics system, The aforementioned driving dynamics system, particularly the primary control unit (M-ECU), is configured to selectively reduce pressure from at least one hydraulically operable wheel brake via the associated outlet valve or via the special solenoid valve (MV2k). A driving dynamics system characterized by the following.

2. The at least one braking pressure regulating valve is a special solenoid valve (MV2k) equipped with an electromagnetic drive device having a first excitation coil (SP1, SP1a), wherein the valve operating member (7) or valve tappet (7a) is displaceable between the valve open position and the valve closed position via the first excitation coil (SP1, SP1a), The special solenoid valve (MV2k) has a force-applying device which includes a permanent magnet (PM) and / or at least one second excitation coil (SP1b, SP2) and is arranged to form at least one holding force (FEM2, FPM) acting on the valve operating member (7) or the valve tappet (7a), and / or The primary control unit (M-ECU) is configured to drive and control the special solenoid valve (MV2k) and the first pressure supply unit (BM1) in at least one of the selected braking modes such that the pressure is reduced when the special solenoid valve (MV2k) is released from the wheel brakes (RB1 to RB4) associated with the special solenoid valve (MV2k). The driving dynamics system according to claim 1.

3. The primary control unit (M-ECU) is configured to drive and control the associated special solenoid valve (MV2k) and the associated outlet valves (AV1 to AV4) in at least one of the selected braking modes, so that brake fluid is simultaneously discharged from the wheel brakes via the associated special solenoid valve (MV2k) and the associated outlet valves (AV1 to AV4). The driving dynamics system according to claim 1 or 2.

4. At least one second pressure supply unit (BM2) is provided, arranged with respect to the first brake circuit (BK1) and the second brake circuit (BK2) to supply brake fluid to at least one input side of the first pressure supply unit, wherein the second pressure supply unit (BM2) preferably includes a piston cylinder unit or a rotary pump, where, Preferably, at least one separation valve is provided to separate the first brake circuit and / or the second brake circuit. A driving dynamics system according to any one of claims 1 to 3.

5. The first pressure supply unit (BM1) is connected (directly) to exactly two wheel brakes (RB1-RB4), and the exactly two wheel brakes (RB1-RB4) brake the wheels provided on the first axle, and / or A separate pressure supply unit (BM3) is provided, which is (directly) connected to at least two wheel brakes (RB1 to RB4) located on the second axle. A driving dynamics system according to any one of claims 1 to 4.

6. The special solenoid valve (MV2k) is configured to be open when no power is supplied, and the valve seat of the special solenoid valve is arranged to be (directly) connected to at least one of the wheel brakes (RB1 to RB4). A driving dynamics system according to any one of claims 1 to 5.

7. The primary control unit (M-ECU) is configured to detect a failure in at least one wheel brake circuit, including one of the wheel brakes (RB1 to RB4), and to close a special solenoid valve (MV2k) associated with the wheel brake (RB1 to RB4) in order to isolate the wheel brake circuit. A driving dynamics system according to any one of claims 1 to 6.

8. The first pressure supply unit (BM1) includes a rotary pump connected and configured to increase or decrease the pressure of the wheel brakes (RB1 to RB4), A driving dynamics system according to any one of claims 1 to 7.

9. The special solenoid valve (MV2k), in particular the special solenoid valve (MV2k) associated with the second pressure supply unit (BM2), is arranged such that the valve seat of the special solenoid valve is (directly) connected to the input side of the first pressure supply unit (BM1). A driving dynamics system according to any one of claims 1 to 8, and more particularly according to claim 4.

10. When the pressure is reduced, at least one of the special solenoid valves (MV2k) is driven and controlled, particularly by PWM drive control or current closed-loop control, so that a variable valve opening cross-sectional area is formed. A driving dynamics system according to any one of claims 1 to 9, particularly according to claim 4 or 9.

11. The actuators of the first secondary control unit (S-ECU1) and / or the second secondary control units (S-ECU2a, S-ECU2b), and / or the first pressure supply unit (BM1) and / or the second pressure supply unit (BM2), and / or the sensors of the first pressure supply unit (BM1) and / or the second pressure supply unit (BM2) are communicateable to the primary control unit (M-ECU), particularly via communication interfaces (IntBM1, IntBM2), in order to execute steering commands and / or braking commands. A driving dynamics system according to any one of claims 1 to 10.

12. The aforementioned primary control unit (M-ECU) is By driving and controlling at least one of the special solenoid valves of the first pressure supply unit and / or at least one of the second pressure supply units, individual pressure control is performed for each wheel brake, and / or When the special solenoid valve of the first pressure supply device or inlet valve is closed, a wheel circuit fault is detected by pressure measurement, and / or By closing at least one of the separation valves (TV1, TV2), the defective brake circuit is isolated, and / or ABS (per axle) is performed by controlling at least one of the separation valves (TV1, TV2) and by alternating pressure increases and decreases via the second pressure supply unit, and / or By controlling at least one of the special solenoid valves (MV2k) and in particular the outlet valve of the first pressure supply unit, and by alternating pressure increases and decreases, individual ABS is performed for each wheel via the second pressure supply unit (BM2), and / or During braking using the at least one traction motor, the braking torque generated by the second pressure supply unit (BM2) is distributed to each axle by controlling a special solenoid valve (MV2K) associated with the second pressure supply unit, and / or (Automatic) emergency braking is performed by driving and controlling the traction motors (TM1, TM2) and at least the first pressure supply unit (BM1) in parallel. It is structured in such a way. A driving dynamics system according to any one of claims 1 to 11, particularly according to claim 11.

13. The electromagnetic drive device (EM1) is redundantly configured with at least one first solenoid valve driver and a second solenoid valve driver. The secondary control unit (S-ECU1) is communicatively connected to the first solenoid valve driver to control the at least one special solenoid valve (MV2k), and the primary control unit (M-ECU) is communicatively connected to the second solenoid valve driver to control the at least one special solenoid valve (MV2k). A driving dynamics system according to any one of claims 1 to 12, and more particularly according to claim 2.

14. The primary control unit (M-ECU) is configured to at least temporarily adjust the braking pressure in the selection of the wheel brakes (RB1 to RB4) using the multiplex method and / or the PPC method. A driving dynamics system according to any one of claims 1 to 13.

15. The primary control unit (M-ECU) is configured to perform at least the method described in claim 16. A driving dynamics system according to any one of claims 1 to 14.

16. Preferably, a method for adjusting the braking pressure in at least one wheel brake of a brake system via an inlet valve for introducing brake fluid into a wheel brake and an outlet valve for releasing brake fluid from the wheel brakes (RB1 to RB4), The said method, To determine that the pressure should be reduced from at least one of the aforementioned wheel brakes (RB1 to RB4), i.e., the target wheel brake, Selecting a decompression mode from the first decompression mode and the second decompression mode, When the first decompression mode is selected, in order to perform decompression, at least one of the outlet valves associated with the target wheel brake is opened, When the second depressurization mode is selected, the outflow valve associated with the target wheel brake is kept closed, at least one of the inflow valves associated with the target wheel brake is opened, and a pressure difference is formed in the (external) preferably second pressure supply unit in order to depressurize the target wheel brake through the inflow valve. Methods that include...

Images