DE202019107193U1 - Braking device, in particular for electrically powered motor vehicles - Google Patents

Abstract

Braking device for a motor vehicle with two axles (A1, A2), at least one axle (A1, A2) having an electric traction motor (TM) for driving and braking the at least one wheel arranged on the axle (A1, A2), and energy can be recovered by means of the traction motor (TM) during braking, - each wheel has a wheel brake (RB1, RB2, RB3, RB4; H-EMBi; EMBi), - a pressure supply (DV) with one driven by an electric motor (M) Pump (P), in the form of a piston-cylinder unit or a rotary pump (ZRP), - the pressure supply (DV) can both build up pressure and reduce pressure, in particular by moving the piston of the piston-cylinder piston back and forth Unit or reversal of the direction of rotation of the rotary pump and at least one pressure supply outlet (DVa), - the pressure supply (DV) is part of a pressure supply device (DV1), the pressure supply device (DV1) having at least two output lines (VLa1, V La2) and at least two connections (VLb1, VLb2) for connection either to the brake circuits (BK1, BK2), an ABS / ESP unit (ABS / ESP) and / or an actuation unit (BE), and - each connection (VLb1 , VLb2) can be separated from the pressure supply (DV) by means of at least one switching valve (SVA1, SVA2), - each output line (VLa1, VLa2) is hydraulically connected to the pressure supply output (DVa) directly or via a connecting line (VLd), - a control - and control device (ECU) controls the at least one electric traction motor (TM) as well as the components of the pressure supply device (DV1) in such a way that in interaction of the pressure supply device (DV1, DV2) and the at least one electric traction motor (TM1, TM2, TM3) for each Brake circuit (BK1, BK2), each axle (A1, A2) or the wheel brakes of an axle (A1, A2) individually, ie with different braking torques on the respective axles (A1, A2) or wheel brakes of an axle (A1, A2), one Brake valve delay can be adjusted.

Description

The present invention relates to a braking device for a motor vehicle with two axles, at least one axle having an electric traction motor for driving and braking the at least one wheel arranged on the axle, and energy can be recovered by means of the traction motor during braking, each wheel having a wheel brake, has, a pressure supply is provided with a pump driven by an electric motor, in the form of a piston-cylinder unit or a rotary pump, the pressure supply can both build up pressure and reduce pressure, in particular by moving the piston back and forth in the piston-cylinder Unit or reversal of the direction of rotation of the rotary pump, and at least one pressure supply outlet.

State of the art

Out WO2018215397A1 a braking system for the recuperation of kinetic energy via the electric drive motor on a first axis is known, the second axis being connected to the actuation unit. It is also off WO2018215397A1 a recuperation brake management system with an electric motor and brake system on one axle is known.

PPC pressure controls with electrically driven piston-cylinder systems using pressure volume characteristics, current and piston position are, for example, off EP 1874602 B1 , DE 102005055751 B3 , DE 102005018649 B3 , DE 102005063659 B3 and EP 1907253 B1 and the multiplex pressure control EP 1874602 B1 and DE 102005055751 B3 known.

So revealed_ DE 102005055751 B3 a brake system in which the pressure change in the wheel brakes takes place using a pressure volume characteristic curve, the piston control being carried out by measuring the motor current and / or determining the position of the piston (so-called PPC pressure control), with each wheel brake being assigned a switching valve and that of the wheel brake during the pressure change assigned switching valve is permanently open. The respective switching valve is closed to hold pressure in the respective wheel brake.

The DE 102005018649 B3 further discloses that a characteristic map is used for pressure control, which is adapted during operation. The purpose of the adaptation is to record changes in operation, such as changes in the pressure-volume characteristic curve, due to air pockets in the hydraulic medium of the brake system.

The DE 102005063659 B3 discloses a_pressure control via current control and amplifier characteristic. With current control, the linear relationship between motor current (phase current) and motor torque, the so-called torque constant, is used in pressure control and / or diagnosis when no pressure transducer is available as a measurement signal.

The EP1907253B1 discloses a brake system with an actuation device, in particular in the form of a brake pedal, the brake system having a control and regulating device which controls an electromotive drive device based on the movement and / or position of the actuation device, the drive device via a piston of a piston-cylinder system a non-hydraulic transmission device that is permanently coupled to the piston is adjusted so that a pressure is established in the working chamber of the cylinder, the working chamber being connected to a wheel brake via a pressure line. A valve controlled by the control and regulating device is arranged in the pressure line to each wheel brake, the actuating device adjusting the piston or the drive device if the drive device fails. The electromotive drive device adjusts the piston via a rotor and a spindle drive acting as a reduction gear, so that the piston generates the pressure change required for the brake force boost and the anti-lock braking system (ABS). The valve closes after the required brake pressure has been reached in the brake cylinder and is also open in ABS operation to set a new lower and a new higher brake pressure.

Object of the invention

Providing a braking system that is simple, fail-safe and inexpensive and can be used for driving dynamics systems with a central control of a vehicle for braking interventions in two brake circuits together with recuperation of kinetic energy via electric motors in electric axle drives and can optionally be expanded with the integration of steering systems.

This object is advantageously achieved with a brake system having the features of claim 1. Advantageous further developments of the brake system according to claim 1 result from the features of the subclaims.

The brake system according to the invention is advantageously characterized in that it has a central brake management system with a central control and regulating device ( M-ECU _BM ) as well as slave control and regulation devices (E-ECU _i ) for the electric axle drive motors ( TM1 , TM2 ) and electrically driven pressure supply devices ( DV1 , DV2 ), so that target braking torques for the electric traction motor (s) and for the hydraulic wheel brakes and thus for the pressure supply device can be specified on several axles or several wheel brakes of an axle. The central brake management can be in a control and regulating device separate from the pressure supply device ( M-ECU _BM ) or the control and regulation unit ( S-ECU _DV1 ) the pressure supply device contains or forms the central brake management. The central brake management can be a software module of a central driving dynamics control according to the domain structure of modern electrically powered vehicles.

The brake system according to the invention can regulate the brake pressures individually for each brake circuit and also additionally with an electric drive motor, which is also referred to below as an electric traction motor, or several electric drive motors, which is or are arranged on the front axle and / or rear axle of a motor vehicle, generate a deceleration torque and at the same time convert kinetic energy into electrical energy via braking using the traction motor or motors and thus recover it (recuperation).

The braking system according to the invention can advantageously be designed in such a way that in an embodiment A with the at least one traction motor and the pressure supply device in interaction for each axle a braking deceleration can be adjusted for each axle, or in an embodiment B in interaction with two wheel brakes of an axle a braking deceleration can be adjusted for each wheel individually.

In embodiment A (2-channel braking force control), an axle-specific control in terms of electrical braking force distribution (EBV) or simplified axle-based ABS for 4-wheeled vehicles or ABS function for 2-wheeled vehicles with recuperation using at least one electric motor combined.

In embodiment B (2x2-channel braking force control), the individual wheel deceleration of an axle is combined with recuperation from an electric drive motor of the axle, whereby in addition to embodiment A, torque vectoring, steering, ABS / ESP functions can be implemented in the axle. An electric power steering on the axle and control of the steering via the central management can also be integrated and the steering function of the brake system by yaw moment control in embodiment B is used as redundancy for electric power steering or to improve agility. In this way, if the electric power steering fails during operation, driving stability can be maintained by the brake. In addition, both the power steering and the brake system can be used to intervene in the driving dynamics to improve agility, especially in vehicles with very high performance or agility requirements, e.g. steering on the front axle via the electric power steering and torque vectoring interventions on the Rear axle of a vehicle. In the second embodiment B, one or more drive motors of an axle, e.g. axle drive by means of one or two motors, steering systems on the front axle and optionally also rear axle, wheel hub electric motors on each wheel, can be provided, and identical or different solutions can be combined on different axles. A 2-channel control module is preferably provided for each axle for a black-and-white braking force distribution with the advantages of short hydraulic lines between the pressure supply and the brake. This design is predestined for e-axles. If a diagonal brake force distribution is mandatory, each 2-channel control module can also provide wheel brakes for the front and rear axles in a typical diagonal brake force distribution with the disadvantage that hydraulic lines have to be routed through the vehicle.

In both embodiments, the pressure in the closed brake circuit is set or regulated in the PPC method by means of the pressure supply device and in normal operation, ie different wheel pressures in the brake circuits, according to the disclosure of FIG EP1907253B1 , the pressure in the brake circuits is set or regulated simultaneously, with a time delay, in particular using the multiplex method or partially simultaneously, ie with a time overlap. For this purpose, the brake system according to the invention has two connecting lines which connect the pressure supply to the two brake circuits, a switching valve for optionally closing and opening the respective connecting line being arranged in each connecting line. For safety reasons, the switching valves can preferably be designed in such a way that the respective hydraulic outlet on the ball valve seat of the switching valves is connected to the wheel brake via a hydraulic line, so that in the event of a fault the pressure in the wheel brake opens the solenoid valves automatically and the brake pressure can always be safely reduced in the event of a fault. The switching valve can be permanently open to the associated brake circuit for the duration of the pressure change, the pressure change then being made with the pressure supply of the pressure supply device.

In addition or as an alternative to the multiplex control, the pressure supply can also provide a pressure in which the PPC method is combined with PWM control or current regulation of the switching valves. As a result, the pressure in one brake circuit is regulated or controlled by pre-pressure control via the pressure supply in the PPC process with the switching valve open, and the switching valve in the other brake circuit is pulse-width modulated or controlled with current. As a result, it is also possible that different pressures can be set or regulated simultaneously or partially simultaneously in both brake circuits and thus different pressure change profiles can be realized at the same time. The pressure curve control is useful for finely dosed EBV control or axis-by-axis ABS control as well as for precise coordination of the braking torques, which are generated by the pressure supply, with the braking torque curve of electric motors.

The multiplex method and / or the PWM control method of the solenoid valves offer all the degrees of freedom of a high-precision brake circuit-specific control while at the same time providing a high level of error safety for a closed brake circuit. In this way, sleeping errors are advantageously avoided and a good, simple and reliable diagnosis of leaks is possible. To use the PWM or current control method, the solenoid valves must be designed as normally open switching valves so that a variable opening cross-section can be set by regulating the voltage of the solenoid valve coils.

The pressure supply device can also be used to implement simplified control functions, i.e. simplified ABS control mode for each axle (embodiment A), in which the wheel pressures are controlled for each axle, but not for each individual wheel. This simplification combined with the high-precision PPC pressure control is sufficient for various applications, such as two-wheelers and racing vehicles with two axles, where ABS / ESP control is not permitted. With the axle-specific braking force control (EBV function), stronger decelerations can be achieved on all wheels than with a pure Select-Low control, since the braking force distribution can be divided according to the axle load distribution on the front and rear axles, i.e. on the rear axle in the event of severe decelerations a lower pressure set than on the front axle. With road vehicles, too, the individual axle control only leads to restrictions only in µ-Spit operation, i.e. when the wheels on one right / left side of the vehicle are on ice and the wheels on the left / right side are on asphalt. In this case, the pressure is adjusted so that none of the wheels lock. This leads to longer braking distances, but the vehicle can still be steered.

By means of embodiment B of the braking system according to the invention in one axle, individual wheel control can be carried out, whereby the system then has all degrees of freedom. Embodiment B enables ABS / ESP for each wheel as well as the anti-slip control function (ASR), torque vectoring and steering interventions. The second embodiment B offers all the degrees of freedom for an axle actuator and can be used in modern electric axle modules with a powerful electric traction motor and can also be easily expanded with additional valve switching to include additional hydraulic actuators in the e-axis (e.g. actuation of clutches of double clutch systems one of the 2-speed transmissions, which are preferably used in modern electric vehicles and is part of a vehicle axle) with pressure. Since gear shifting and braking do not take place at the same time, the MUX operation of the brake and clutch does not lead to any functional restrictions.

It is also possible that the brake system according to the invention of the first embodiment A is designed with an already known standard ABS / ESP unit, which is interposed between the pressure supply device and the brake circuits. The ABS / ESP function takes over the individual wheel control and the braking system according to the invention can still enable the axle-specific brake pressure control / axle-by-axle ABS function) with recuperation if the ABS / ESP unit fails, which means that the redundancy requirements for various levels of autonomous driving (AD ) Level 3 and level 4 (see ATZ article Brake booster for autonomous driving, issue 3/19) can be fulfilled. In addition, both brake modules can be applied separately and obtained from different suppliers, whereby the central brake management ( M-ECU _BM ) preferably takes place in the brake system according to the invention of the first embodiment A.

• - vorteilhafte Möglichkeit der Einbindung des Bremssystems und deren Bremsenregelung in eine Domänenstruktur einer zentralen Fahrdynamikregelung mit der Möglichkeit der Optimierung der gesamten Fahrdynamik und Einbindung mehrerer Stellaktuatoren für Bremse, Lenkung und Dämpfung sowie Einbindung der elektrischen Traktionsmotoren;
• - Zentralsteuerung vom mindestens einem elektrischen Antriebsmotor und hydraulischer Bremse kann vorteilhaft zur Optimierung des Verschleißes von mechanischen Teilen genutzt werden. So kann der Verschleiß des Bremssattels sowie die Erwärmung von Bremssatteln durch Aufteilung der Bremsenergie auf die mechanisch/hydraulische Bremse und den mindestens einen elektrischen Antriebsmotor bzw. Traktionsmotor, welcher aufgrund typischer Wasserkühlung Wärme sehr gut abführen kann, reduziert werden. Damit können Fadingeffekte reduziert werden und das hydraulische Bremssystem kann auf geringere Drücke ausgelegt werden, wodurch die Druckversorgung downgesized werden kann. z.B. kann der Antriebsmotor für die Druckversorgung auf ein geringes Drehmoment ausgelegt werden. Zudem können die Lastzyklen mit maximaler Belastung reduziert werden und die mechanischen Komponenten, wie z.B. Spindeltrieb, Kolbendichtungen, können einfacher ausgeführt werden, da eine geringe hydraulische Belastung auf die Druckversorgung wirkt. Auch ist es denkbar, ein einfaches Getriebe, wie z.B. eine Trapezspindel aus Kunststoff, oder ein Kunststoffgehäuse für die Druckversorgung einzusetzen und/oder als Druckversorgung eine kostengünstige Rotationspumpe einzusetzen. Dies erfordert jedoch einen sehr starken elektrischen Antriebsmotor mit einer Leistung von größer 100 kW. Dieses oben beschriebene Downsizingpotential kann jedoch durch anderer Regelanforderungen, z.B. lang andauerndem Anti-Schlupf-Regelbetrieb (ASR) bei Fahrbahnen mit unterschiedlichen Reibwerten zunichte gemacht werden, da hier ein dauerhafter Betrieb bei hohen Drücken erfolgt. Dieses Downsizingpotential ist daher ggf. begrenzt auf Fahrzeuge im autonomen Fahrbetrieb mit reduzierten Geschwindigkeiten in bestimmten Klimazonen, wo keine kritischen ASR-Anforderungen erfüllt werden müssen (z.B. Fahrzeugbetrieb in Indien)

• - die vorteilhafte Multiplexregelung (MUX-Regelung) oder die präzise PPC-Regelung mit PWM-Steuerung der Ventile ist beim Druckaufbau und/oder Druckabbau einsetzbar und ermöglicht somit sehr viele Freiheitsgrade in der präzisen Druckregelung mehrerer hydraulischer Stellglieder. Zudem ist eine Kombination von MUX-Regelung und PPC/PWM-Regelung möglich, wodurch eine sehr präzise Abstimmung auf den mindestens einen elektrischen Antriebsmotor möglich ist und gleichzeitig bremskreisindividuelle Bremsdrücke eingestellt werden können;
• - die EBV-Funktion, d.h. die elektrische Bremskraftverteilung zwischen Vorderachse und Hinterachse, kann deutlich einfacher und mit höherer Regelgüte als bei bekannten Bremssystemen im Markt, z.B. auf Basis MKC1-Bremssystem gemäß DE102013224313A1 oder Bremssystem gemäß US9981645B2 , umgesetzt und appliziert werden, da in den bekannten Bremssystemen das PPC-Verfahren, die MUX-Regelung sowie PWM-Steuerung von Auslassventilen in Druckauf- und Druckabbau nicht genutzt wird oder aufgrund Einschränkungen des Hydraulikkonzeptes nur teilweise genutzt werden kann. Beispielweise erfordert das MUX-Verfahren Ventile, die den Druck halten müssen. Dies ist durch die Parallelschaltung von Rückschlagventilen zu den Schaltventilen beim Druckabbau nicht möglich. Gleichzeitig kann der erfindungsgemäßen zentralen Fahrdynamikregelung das Bremsmoment der Elektromotoren zur Verstärkung der Dynamik sowie Maximierung des Bremsmomentes in der Achsbremsmomentverteilung ergänzend genutzt werden. Hierdurch ist eine Optimierung der Bremsverzögerung unter Berücksichtigung unterschiedlicher Achslasten, z.B. bei starker Verzögerung signifikant höhere Drücke an Vorderachse, bzw. daraus resultierend unterschiedlicher Bremsmomentverteilungsbedarf an den Achsen möglich; dieses Merkmal hat Bedeutung bei Rennfahrzeugen, z.B. Rally-Fahrzeugen mit elektrischen Antrieben an Vorder- und Hinterachse oder sog. Super Cars oder Hyper Cars mit Antriebsleistungen > 300 kW mit zugleich hohen Dynamikanforderungen.

• - vorteilhafte Möglichkeit der Optimierung der Bremsmomentaufbaudynamik durch gleichzeitige Nutzung des hydraulischen Bremssystems und der Elektromotoren, wodurch z.B. eine kürzere Zeit zum Erreichen des Blockierdruckes, insbesondere bei Notbremsfunktionen, erzielbar ist;
• - Optimierungsmöglichkeit der Rekuperationsleistung über die Elektromotoren, derart, dass in gewissen Situationen bei niedrigen Fahrzeuggeschwindigkeiten <120 km/h ausschließlich bzw. weitestgehend, insbesondere mehr als zweidrittel (2/3) der Verzögerung, über den einen oder beide elektrische Antriebsmotor(en) (Traktionsmotor(en)) erzielbar sind, z.B. bei geringen Fahrgeschwindigkeiten. Die Verzögerungsleistung ist dabei begrenzt durch die max. Leistung und das maximale Drehmoment des Elektromotors;
• - eine einfache und sichere Regelung der Bremsdrücke über die Druckversorgungseinrichtung im Multiplexbetrieb (MUX-Betrieb) mit sehr geringem Ventilaufwand im zugleich geschlossenen Bremskreis, d.h. ohne Auslassventile, die im Regelbetrieb die Bremskreise mit dem Vorratsbehälter verbinden, ist möglich. Der Entfall von Auslassventilen hat den Vorteil, dass die Bremskreise im aktiven Betrieb mit dem Vorratsbehälter nicht hydraulisch verbunden werden und damit können unerkannte Undichtigkeiten bei Ventilen, z.B. durch Schmutzpartikel im Ventilsitz (schlafende Fehler) vermieden bzw. diagnostiziert werden, was die Zuverlässigkeit erhöht;
• - Das Bremssystem hat in bestimmten Ausführungsformen des erfindungsgemäßen Systems, siehe insbesondere die in den 3 und 3a gezeigten und beschriebenen Ausführungsformen, eine sehr hohe Verfügbarkeit durch die nachfolgend aufgeführten Redundanzen, welche einzeln oder in Kombination oder alle bei dem erfindungsgemäßen Bremssystem vorgesehen werden können:
  1. a) redundante und zugleich diagnostizierbare Dichtungen in sowohl der Betätigungseinheit und Druckversorgung,
  2. b) redundante 2x3 Phasen-Kontaktierung der Anschlüsse des Elektromotors der Druckversorgung,
  3. c) redundante in Reihe geschaltete Ventile zwischen Druckversorgung und Bremskreis bzw. zwischen Betätigungseinheit und Bremskreis,
  4. d) redundante Bordnetzanschlüsse der Slave-ECUs,
  5. e) Redundanz durch Bremsen über Elektromotor bei Ausfall oder Teilausfall der Druckversorgung.
  6. f) Redundante Datenübertragung z.B. durch über redundante kabelgebundene Datenübertragung oder kabellose Datenübertragung mit hohem Sicherheitsstandard (z.B. mit Datenübertragungsmöglichkeiten mit geringer Latenzzeit, z.B. 5G-Funktdatenübertragung oder neuen Bluetooth-Protokollen erfolgen) bzw. Kombination von kabelgebunden und kabelloser Datenübertragung
  Die Merkmale a) bis f) erfüllen die Sicherheitsanforderungen einer reinen Brake-by-Wire mit E-Pedal bzw. Fahrzeugen ohne Betätigungseinheit, d. h. fahrerlose Fahrzeuge;
• - eine sehr gute Diagnosemöglichkeit der hydraulischen Fehler, wie z.B. Undichtigkeiten oder Bremskreisausfall, ist durch die Ausführung als geschlossenes System (keine schlafenden Fehler) möglich und die Diagnose durch Druckaufbau über die Druckversorgung ist ebenso möglich;
• - die Druckversorgung kann alternativ als eine über einen Elektromotor und eine nicht-hydraulische Getriebevorrichtung angetriebene Kolben-Zylinder-Einheit oder eine über einen Elektromotor angetriebene Rotationskolbenpumpe, insbesondere einer Zahnradpumpe, ausgebildet werden, die dadurch gekennzeichnet ist, dass die Druckversorgung in beiden Ausführungsformen unter Verwendung entweder einer Kolbenpumpe oder einer Rotationspumpe sowohl Druck aufgebaut als auch Druck abgebaut werden kann und somit die oben beschriebenen Regelverfahren eingesetzt werden können. Bei Verwendung einer Zahnradpumpe ist der Begriff PPC-Druckregelverfahren nicht zutreffend, die Regelung erfolgt anstatt über die Kolbenposition über eine Winkelposition der Rotationspumpe und entspricht damit einem verdrängten Volumen, wobei vorteilhaft die Druck-Volumen-Kennlinie und der Motorstrom bei beiden Verfahren für die Druckregelung genutzt werden können. Bei Verwendung einer Zahnradpumpe muss zusätzlich die prinzipbedingte Leckage der Rotationspumpe erkannt und in der Regelung berücksichtigt werden.
• - es besteht vorteilhaft, bei ausreichender Redundanz der Betätigungseinheit (red. Dichtungen) oder der Slave-Bremskrafterzeuger (Motoren, red. Druckversorgung), eine mechanische Rückfallebene, wobei die Betätigungseinheit vorteilhaft sehr einfach als einfacher kostengünstiger und kurzbauender Hauptbremszylinder ausgeführt werden kann; Dies hat eine hohe Bedeutung, insbesondere weil die Baulänge das Kofferraumvolumen eines E-Fahrzeuges beeinflusst und aus Crash-Gesichtspunkten aufgrund der Anbindung an der Spritzwand eines Fahrzeuges ein kritischer Auslegungspunkt ist.
• - Das Bremssystem kann vorteilhaft modular für verschiedene Ausführungsformen aufgebaut sein, wobei nachfolgend einige mögliche Modulbauweisen aufgezählt werden:
  • a. zentrales Bremsenmanagement als separate Einheit oder Modul einer zentralen Domäne des Fahrdynamikmanagements oder Bestandteil der Druckversorgungseinrichtung bzw. deren Steuereinheit;
  • b. einzelne Module, die bedarfsweise zusammengenommen und in verschiedenen Anordnungen zusammengefügt sind, wie z.B. aufgelöstes System mit separater Betätigungseinheit und separate Regeleinheit;
  • c. aufgelöstes System mit separater Betätigungseinheit;
  • d. aufgelöstes System mit E-Pedal und separater redundanter Regeleinheit und redundanter Datenübertragung;
  • e. integrierte Einheit, wobei Betätigungseinheit und Druckversorgung mit 2-kreisiger Regelung in einem Modul zusammengefasst sind;
  • f. Druckversorgung gebildet durch eine über einen Elektromotor und Getriebe angetriebene Kolben-Zylinder-Einheit oder gebildet durch eine über einen Elektromotor angetriebene Rotationspumpe, insbesondere in Form einer Zahnradpumpe;
  • g. gesonderte ABS-Einheit bzw. Raddruckregeleinheit, die Bremskreisdrücke auf verschiedene Räder aufteilt, einfach gestaltbar sowie anschließbar die als Modul ausgebildete Druckversorgungseinrichtung anschließbar, wobei diese separat applizierbar auch für radindividuelle Regelung an den Achsen ist;
  • h. ABS/ESP-Regeleinheit als Standalone-System mit eigener Druckversorgung (Redundanz) oder einfache Ventilregeleinheit unter Nutzung der Vordruckregelung durch das Bremssystem;
  • j. Betätigungseinheit in separatem Gehäuse, abnehmbar von der Druckversorgung für aufgelöstes System, wobei die Druckversorgung parallel zur Betätigungseinheit angeordnet ist; k. Druckversorgung als Rotationskolbenpumpe, wobei die Achse der Rotationspumpe senkrecht zur Achse der Kolben-Zylinder-Einheit der Betätigungseinheit ausgerichtet ist, wobei die Rotationspumpe und Magnetventile in einer Baueinheit integriert sind.
  • l. vollvariables Bremssystem für den Einsatz in einem Elektro-Achsmodul einer Elektroachse für ABS/ESP, Torque Vektoring, Lenkungseingriffe sowie gleichzeitiger Rekuperationsregelung über Elektromotoren und damit mit allen Freiheitgraden versehen für dynamischen und zugleich präzisen radindividuellen Druckregelung bei gleichzeitiger hoher Fehlersicherheit, Redundanzen und geschlossen Bremskreis. Während Lösungen gemäß Stand der Technik, z.B. WO2018/130406 , durch den Magnetventilen der Radbremsen parallel geschaltete Rückschlagventile nicht die Möglichkeit bieten, Drücke in Rädern zu halten und gleichzeitig in anderen Rädern die Drücke zu reduzieren, hat das erfindungsgemäße Achsmodul keinerlei funktionale Einschränkungen und zudem ein höhere Regeldynamik. Dies erleichtert die Entwicklung, Applikation und Optimierung einer zentralen Fahrdynamikregelung mit Brems- und Lenkungseingriffen bei gleichzeitiger Rekuperation über Elektromotoren ohne Abhängigkeit von Einschränkungen bestehender Systemlösungen. Zudem ist ein derartiges Modul kombinierbar mit unterschiedlichen Systemlösungen an weiteren Achsen, z.B. elektromechanische Bremse H-EMB mit hydraulischer Druckversorgung als Redundanz, zweites Achsmodul mit dem gleichen Aufbau wie am ersten Achsmodul mit Differenzierung in einem kostengünstigeren Aufbau der Druckversorgung und gut integrierbar in eine reine Brake-by-Wire-Lösung mit E-Pedal bzw. zentraler Fahrdynamiksteuerung eines fahrerlosen Fahrzeuges (Robo-Taxi) ohne Betätigungseinheit.

Special advantages of the braking system according to the invention are explained in greater detail below:

• - Advantageous possibility of integrating the brake system and its brake control into a domain structure of a central driving dynamics control with the possibility of optimizing the entire driving dynamics and integrating several actuators for brakes, steering and damping as well as integrating the electric traction motors;
• - Central control of at least one electric drive motor and hydraulic Brake can be used advantageously to optimize the wear and tear on mechanical parts. The wear of the brake caliper and the heating of the brake caliper can be reduced by dividing the braking energy between the mechanical / hydraulic brake and the at least one electric drive motor or traction motor, which can dissipate heat very well due to typical water cooling. This allows fading effects to be reduced and the hydraulic brake system can be designed for lower pressures, whereby the pressure supply can be downsized. For example, the drive motor for the pressure supply can be designed for a low torque. In addition, the load cycles with maximum load can be reduced and the mechanical components, such as, for example, spindle drive, piston seals, can be designed more simply, since a low hydraulic load acts on the pressure supply. It is also conceivable to use a simple gear, such as a trapezoidal spindle made of plastic, or a plastic housing for the pressure supply and / or to use an inexpensive rotary pump as the pressure supply. However, this requires a very powerful electric drive motor with an output of more than 100 kW. This downsizing potential described above can, however, be nullified by other control requirements, for example long-term anti-slip control operation (ASR) on roads with different coefficients of friction, since permanent operation takes place at high pressures. This downsizing potential is therefore limited to vehicles in autonomous driving operation at reduced speeds in certain climate zones where no critical ASR requirements have to be met (e.g. vehicle operation in India)

• - The advantageous multiplex control (MUX control) or the precise PPC control with PWM control of the valves can be used for pressure build-up and / or pressure reduction and thus enables a great deal of freedom in the precise pressure control of several hydraulic actuators. In addition, a combination of MUX control and PPC / PWM control is possible, as a result of which a very precise adjustment to the at least one electric drive motor is possible and, at the same time, individual brake pressures can be set;
• - The EBV function, ie the electrical braking force distribution between the front axle and rear axle, can be performed much more easily and with higher control quality than with known brake systems on the market, for example based on the MKC1 brake system DE102013224313A1 or braking system according to US9981645B2 , implemented and applied, since in the known brake systems the PPC process, the MUX regulation and PWM control of outlet valves in pressure build-up and pressure reduction are not used or can only be partially used due to restrictions in the hydraulic concept. For example, the MUX process requires valves that must maintain the pressure. This is not possible due to the parallel connection of check valves to the switching valves when the pressure is reduced. At the same time, the central vehicle dynamics control according to the invention can also use the braking torque of the electric motors to reinforce the dynamics and to maximize the braking torque in the axle braking torque distribution. This enables the braking deceleration to be optimized, taking into account different axle loads, for example significantly higher pressures on the front axle in the case of strong deceleration, or different braking torque distribution requirements on the axles resulting therefrom; This feature is important for racing vehicles, for example rally vehicles with electric drives on the front and rear axles or so-called super cars or hyper cars with drive powers> 300 kW with high dynamic requirements.

• - Advantageous possibility of optimizing the braking torque build-up dynamics through simultaneous use of the hydraulic brake system and the electric motors, whereby, for example, a shorter time to reach the locking pressure, especially during emergency braking functions, can be achieved;
• - Possibility to optimize the recuperation power via the electric motors, so that in certain situations at low vehicle speeds <120 km / h only or as much as possible, in particular more than two-thirds (2/3) of the deceleration, via one or both electric drive motor (s) ( Traction motor (s)) can be achieved, for example at low driving speeds. The deceleration power is limited by the maximum power and the maximum torque of the electric motor;
• - A simple and safe control of the brake pressures via the pressure supply device in multiplex operation (MUX operation) with very little valve effort in the brake circuit that is closed at the same time, ie without outlet valves that connect the brake circuits to the reservoir in normal operation. The omission of outlet valves has the advantage that the brake circuits are not hydraulically connected to the reservoir during active operation and thus undetected leaks in valves, for example due to dirt particles in the valve seat (dormant faults), can be avoided or diagnosed, which increases reliability;
• - The braking system has in certain embodiments of the system according to the invention, see in particular those in FIGS 3 and 3a shown and described embodiments, a very high availability due to the redundancies listed below, which can be provided individually or in combination or all in the brake system according to the invention:
  1. a) redundant and at the same time diagnosable seals in both the actuation unit and pressure supply,
  2. b) redundant 2x3 phase contacting of the connections of the electric motor of the pressure supply,
  3. c) redundant valves connected in series between pressure supply and brake circuit or between actuation unit and brake circuit,
  4. d) redundant on-board network connections of the slave ECUs,
  5. e) Redundancy through braking via an electric motor in the event of failure or partial failure of the pressure supply.
  6. f) Redundant data transmission, e.g. through redundant wired data transmission or wireless data transmission with a high security standard (e.g. with data transmission options with low latency, e.g. 5G radio data transmission or new Bluetooth protocols) or a combination of wired and wireless data transmission
  Features a) to f) meet the safety requirements of a pure brake-by-wire with an electric pedal or vehicles without an actuation unit, ie driverless vehicles;
• - A very good possibility to diagnose hydraulic errors, such as leaks or brake circuit failure, is possible due to the design as a closed system (no dormant errors) and diagnosis by building up pressure via the pressure supply is also possible;
• - The pressure supply can alternatively be designed as a piston-cylinder unit driven by an electric motor and a non-hydraulic transmission device or a rotary piston pump driven by an electric motor, in particular a gear pump, which is characterized in that the pressure supply is used in both embodiments either a piston pump or a rotary pump both pressure can be built up and pressure can be reduced and thus the control method described above can be used. When using a gear pump, the term PPC pressure control method is not applicable; instead of using the piston position, the control takes place via an angular position of the rotary pump and thus corresponds to a displaced volume, whereby the pressure-volume characteristic curve and the motor current are advantageously used for pressure control in both methods can be. When using a gear pump, the principle-related leakage of the rotary pump must also be recognized and taken into account in the control.
• - It is advantageous, with sufficient redundancy of the actuation unit (red. seals) or the slave brake force generator (motors, red. pressure supply), a mechanical fallback level, wherein the actuation unit can advantageously be designed very simply as a simple, inexpensive and short master cylinder; This is of great importance, in particular because the overall length influences the trunk volume of an electric vehicle and, from a crash point of view, is a critical design point due to the connection to the bulkhead of a vehicle.
• - The braking system can advantageously have a modular structure for different embodiments, some possible modular structures being listed below:
  • a. central brake management as a separate unit or module of a central domain of vehicle dynamics management or part of the pressure supply device or its control unit;
  • b. individual modules that are put together as required and put together in different arrangements, such as a broken-up system with separate actuation unit and separate control unit;
  • c. resolved system with separate actuation unit;
  • d. resolved system with e-pedal and separate redundant control unit and redundant data transmission;
  • e. integrated unit, whereby the actuation unit and pressure supply with 2-circuit control are combined in one module;
  • f. Pressure supply formed by a piston-cylinder unit driven by an electric motor and gearbox or by one driven by an electric motor Rotary pump, in particular in the form of a gear pump;
  • G. separate ABS unit or wheel pressure control unit, which distributes brake circuit pressures to different wheels, can be easily configured and connected, the pressure supply device designed as a module can be connected, whereby this can also be applied separately for wheel-specific control on the axles;
  • H. ABS / ESP control unit as a standalone system with its own pressure supply (redundancy) or simple valve control unit using the pre-pressure control by the brake system;
  • j. Actuating unit in a separate housing, removable from the pressure supply for the resolved system, the pressure supply being arranged parallel to the actuating unit; k. Pressure supply as a rotary piston pump, the axis of the rotary pump being aligned perpendicular to the axis of the piston-cylinder unit of the actuating unit, the rotary pump and solenoid valves being integrated in one structural unit.
  • l. Fully variable braking system for use in an electric axle module of an electric axle for ABS / ESP, torque vectoring, steering interventions as well as simultaneous recuperation control via electric motors and thus provided with all degrees of freedom for dynamic and at the same time precise wheel-specific pressure control with high error safety, redundancies and closed brake circuit. While prior art solutions, e.g. WO2018 / 130406 Because check valves connected in parallel do not offer the possibility of maintaining pressures in wheels and reducing the pressures in other wheels at the same time, the axle module according to the invention has no functional restrictions whatsoever and also has higher control dynamics. This facilitates the development, application and optimization of a central vehicle dynamics control with braking and steering interventions with simultaneous recuperation via electric motors without being dependent on the restrictions of existing system solutions. In addition, such a module can be combined with different system solutions on other axes, e.g. electromechanical brake H-EMB with hydraulic pressure supply as redundancy, second axis module with the same structure as on the first axis module with differentiation in a more cost-effective structure of the pressure supply and can be easily integrated into a pure brake -by-wire solution with e-pedal or central driving dynamics control of a driverless vehicle (robo-taxi) without actuation unit.

Possible areas of application for the braking system according to the invention

• - für Bremssysteme für Rennsportfahrzeuge mit Funktionsumfang der hochdynamischen und präzisen achsweisen Bremsmomentenregelung im Sinne der EBV-Optimierung (EBV = elektronische Bremskraftverteilung) sowie gleichzeitiger Rekuperation über mindestens einen Elektromotor an einer oder zwei Achsen;
• - für Fahrzeuge ohne bzw. mit nur achsweiser ABS-Regelung, z.B. im Rennsport, Versuchsfahrzeuge für die Entwicklung von zentralen Fahrdynamikregelungen mit Elektromotoren an mehreren Achsen oder Fahrzeuge mit geringen Anforderungen an ABS-Regelung, wie z.B. langsam fahrende People-Mover Fahrzeuge;
• - für Fahrzeuge mit sehr hoher Antriebsleistung und hohen Fahrdynamikanforderungen, sog. Super-Cars oder Hyper-Cars, mit elektrischen Traktionsmotoren an mehreren Achsen oder mehreren Rädern einer Achse;
• - für 2-Radfahrzeuge mit je einem Elektromotor an einem Rad, z.B. E-scouter oder Elektro-Pedelecs, wodurch dann eine komplette 2-Rad ABS-Regelung möglich ist. Für die 2-Rad-Lösung wird insbesondere die kostengünstige elektrisch angetriebene Zahnradpumpe mit integrierter Hydraulikeinheit HCU gemäß 2 verwendet, welche derart abgewandelt ist, dass statt einer Achse mit zwei Rädern in einem Bremskreis nur ein Rad vorgesehen ist. Es kann ebenso ein Aufbau der Zahnradpumpe mit integrierter HCU mit Ventilen gemäß 6a, 6b eingesetzt werden. Gegenüber herkömmlichen 2-Rad-ABS-Systemen mit Kolbenpumpe kann der Druck durch PPC-Druckregelung sowie Multiplexbetrieb und PWM-Steuerung der Magnetventile sehr präzise und dynamisch gesteuert werden und optimal auf die Rekuperation über den elektrischen Antriebsmotor an einem Rad abgestimmt werden, wobei zusätzlich die EBV-Steuerung an den Rädern realisiert werden kann. Dies verbessert die Bremsperformance sowie Sicherheit von 2-Radfahrzeugen. Das zentrale Bremsenmanagement ist dann in der ECU der Druckversorgungeinrichtung vorzugsweise integriert.
• - für E-Bikes (Elektro-Pedelecs) mit einem Zentralmotor oder Radnabenmotor, wo durch die erfindungsgemäße Zentralsteuerung eine ABS-Funktion an den beiden Rädern z.B. durch Einbindung Drehmoments eines Radnabenmotors realisiert. Wird ein Zentralmotor eingebunden, ist sicherzustellen, dass der zentrale Antriebsmotor bei ABS-Betrieb kein Antriebsmoment bzw. ein Bremsmoment erzeugt und sich nicht auf den Antriebsmotor auswirkt. Aus Kostengründen wird hier eine kostengünstige Lösung der Druckversorgung in der Ausführungsform als Rotationspumpe mit zwei Schaltventilen präferiert mit entsprechender Einbindung der Bremsanlage (z.B. 2c).
• - für Fahrzeuge mit Elektro-Achsmodulen, z.B. Hinterachsmodul mit einem Traktionsmotor optional ergänzt um lastunterbrechungsfreien 2-Gang-Doppelkupplungsgetriebe für die Achse oder elektrischen Traktionsmotoren für die unterschiedlichen Räder einer Achse mit Rekuperation sowie ABS/ESP-,Torque Vektoring und/oder Lenkungsfunktion z.B. als weiteren Lenkungssteller in Ergänzung einer elektrischen Servolenkung an der Vorderachse. Das erfindungsgemäße Bremssystem kann auch für eine Notlenkungsfunktion bei Ausfall der elektrischen Servolenkung bzw. als Ergänzung zum Lenkungseingriff an einer Achse und/oder an einer zweiten Achse genutzt werden;
• - für kostengünstige Fahrzeuge in BRIC-Ländern, wo achsweise, bremskreisindividuelle Regelung ausreichend ist und optional elektrische oder elektrohydraulische Servolenkung für Fahrzeugstabilisierungszwecke eingesetzt wird;
• - modular ergänzbar mit separat operierender ABS/ESP-Regeleinheit, wobei beide Einheiten dann von separaten Bremsenherstellern bezogen werden können und zudem separat für das Fahrzeug applizierbar sind, wobei die Applikation der primären erfindungsgemäßen Bremsanlage durch den Fahrzeughersteller vorgenommen werden kann.
• - modular einsetzbar in Kombination mit zusätzlichem Radbremsmodul an der zweiten Achse, z.B. Hinterachse, wo beispielsweise eine elektromechanische Bremse (EMB) oder hydraulisch unterstützte elektromechanische Bremse (H-EMB) eingesetzt wird, wobei dann im erfindungsgemäßen Bremssystem die zwei Bremskreise des Bremssystems auf die Räder der Vorderachse aufgeteilt werden, so dass aus dem erfindungsgemäßen Bremssystem ein vollwertiges ABS/ESP-System mit zusätzlichen Freiheitgraden der Lenkungseingriffs und Torque-Vektoring bei gleichzeitiger Rekuperation gebildet werden kann, wobei beide erfindungsgemäße Achsmodule und elektromechanische(n) Bremse(n) EMB in das Bremsenmanagement integriert und zentral gesteuert werden. Diese Variante der erfindungsgemäßen Bremsanlage ist prädestiniert für eine E-Pedallösung bzw. fahrerlose Fahrzeuge ohne Pedal. Alternativ zur EMB bzw. H-EMB an der zweiten Achse kann die erfindungsgemäße Lösung auch für die zweite Achsen dupliziert werden.

The braking system according to the invention can advantageously be used for the following types of vehicles:

• - For braking systems for racing vehicles with the functionality of the highly dynamic and precise axle-wise braking torque control in the sense of EBV optimization (EBV = electronic braking force distribution) as well as simultaneous recuperation via at least one electric motor on one or two axles;
• - For vehicles without or with only axle-based ABS control, e.g. in racing, test vehicles for the development of central vehicle dynamics controls with electric motors on several axles or vehicles with low requirements for ABS control, such as slow-moving people-mover vehicles;
• - For vehicles with very high drive power and high demands on driving dynamics, so-called super cars or hyper cars, with electric traction motors on several axles or several wheels on one axle;
• - for 2-wheel vehicles with an electric motor on each wheel, e.g. e-scouters or electric pedelecs, which then enables complete 2-wheel ABS control. The cost-effective electrically driven gear pump with integrated hydraulic unit is particularly suitable for the 2-wheel solution HCU according to 2 used, which is modified in such a way that instead of an axle with two wheels in a brake circuit only one wheel is provided. A structure of the gear pump can also be integrated HCU with valves according to 6a , 6b can be used. Compared to conventional 2-wheel ABS systems with piston pumps, the pressure can be controlled very precisely and dynamically by PPC pressure control as well as multiplex operation and PWM control of the solenoid valves and optimally matched to the recuperation via the electric drive motor on one wheel, with the EBV control can be implemented on the wheels. This improves the braking performance and safety of 2-wheel vehicles. The central brake management is then preferably integrated in the ECU of the pressure supply device.
• - For e-bikes (electric pedelecs) with a central motor or wheel hub motor, where the central control according to the invention realizes an ABS function on the two wheels, for example by integrating the torque of a wheel hub motor. If a central motor is integrated, it must be ensured that the central drive motor does not have any drive torque or torque during ABS operation. generates a braking torque and does not affect the drive motor. For reasons of cost, a cost-effective solution for the pressure supply in the embodiment as a rotary pump with two switching valves is preferred with a corresponding integration of the brake system (e.g. 2c ).
• - For vehicles with electric axle modules, e.g. rear axle module with a traction motor, optionally supplemented with load-interruption-free 2-speed double clutch transmission for the axle or electric traction motors for the different wheels on an axle with recuperation as well as ABS / ESP, torque vectoring and / or steering function e.g. as further steering actuator in addition to an electric power steering on the front axle. The braking system according to the invention can also be used for an emergency steering function in the event of failure of the electric power steering or as a supplement to the steering intervention on one axle and / or on a second axle;
• - For inexpensive vehicles in BRIC countries, where axle-by-axle, individual brake circuit control is sufficient and electrical or electrohydraulic power steering is optionally used for vehicle stabilization purposes;
• - Modularly supplementable with separately operating ABS / ESP control unit, both units can then be obtained from separate brake manufacturers and can also be applied separately for the vehicle, whereby the application of the primary brake system according to the invention can be carried out by the vehicle manufacturer.
• - Can be used modularly in combination with an additional wheel brake module on the second axle, e.g. rear axle, where, for example, an electromechanical brake (EMB) or hydraulically assisted electromechanical brake (H-EMB) is used, the two brake circuits of the brake system then acting on the wheels in the brake system according to the invention the front axle are divided so that a full-fledged ABS / ESP system with additional degrees of freedom of steering intervention and torque vectoring with simultaneous recuperation can be formed from the braking system according to the invention, with both axle modules according to the invention and electromechanical brake (s) EMB in the Brake management can be integrated and controlled centrally. This variant of the brake system according to the invention is predestined for an e-pedal solution or driverless vehicles without a pedal. As an alternative to the EMB or H-EMB on the second axis, the solution according to the invention can also be duplicated for the second axis.

In the following, possible embodiments of the brake system according to the invention are explained in more detail with reference to drawings.

• 1: eine erste mögliche Ausführungsform eines erfindungsgemäßen Bremssystems mit modularem Aufbau mit Tandem-Hauptbremszylinder THZ und zweikreisiger Rückfallebene in Vorderachse und Hinterachse;
• 1a: eine erste mögliche Ausführungsform eines zentralen Bremsenmanagement für ein Bremssystem für eine Fahrerwunschregelung (FW) oder eine alternative Regelung bei autonomem Fahren (AD-Ctrl);
• 1b: eine weitere mögliche Ausführungsform des Bremssystems, bei dem die Verbindung des zweiten Bremskreises mit der Druckversorgungseinrichtung über die Kolben-Zylinder-Einheit der Betätigungseinrichtung erfolgt und das Schaltventil zwischen der Kolben-Zylinder-Einheit und dem Anschluss der Druckversorgungseinrichtung angeordnet ist;
• 1c: eine weitere mögliche Ausführungsform des Bremssystems, bei dem die Verbindung des zweiten Bremskreises mit der Druckversorgungseinrichtung über die Kolben-Zylinder-Einheit der Betätigungseinrichtung erfolgt und das Schaltventil zwischen der Kolben-Zylinder-Einheit und der Druckversorgung der Druckversorgungseinrichtung angeordnet ist;
• 2a: eine Abwandlung der Ausführungsform gemäß 1 mit einem Single-Hauptbremszylinder mit Verzweigungsschaltung und Hauptbremszylinder mit redundanten diagnostizierbaren Dichtungen aus, sowie einer Gateway-Schaltung;
• 2b: eine Abwandlung der Ausführungsform gemäß 3a, wobei lediglich die Betätigungseinheit in der Rückfallebene auf den zweiten Bremskreis wirkt, und bei der bei Bremskreisausfall durch Bremswirkung der Motoren an der Vorderachse und Hinterachse ein Bremsmoment erzielbar ist;
• 2c: Ausführungsform wie 3b, wobei die Druckversorgung als elektrische angetriebene Rotationspumpe, z.B. Zahnradpumpe ausgebildet ist, wobei die Regelung des Drucks über Winkelgeber (Position der Zahnradpumpe) und Strom (Drehmoment) erfolgen kann;
• 3: fehlersichere redundante Ausführungsform mit E-Pedal für Rekuperation und achsweise Druckregelung im MUX und PWM-Betrieb;
• 3a Elektro-Achslösung mit zentraler Steuerung mit radindividueller Regelung und mehrfachen Redundanzen in Bremssystem;
• 3b eine Querschnittsdarstellung durch eine hydraulisch unterstützte elektromechanische Bremse H-EMB;
• 4: Ausführungsform gem. 1c ergänzt um separat operierende ABS/ESP-Einheit;
• 5: Druckversorgung mit 2x3-Phasen und red. diagnostizierbare Dichtungen;
• 6a, 6b: Druckversorgungseinrichtung mit im Elektromotor integrierter Rotationspumpe und HCU;
• 7a: 2-Kanal Druckaufbauregelung mit PPC-Regelung und mit zusätzlich PWM-Steuerung eines Ventils, das die Druckversorgung DV mit Hinterachse verbindet;
• 7b: 2-Kanal Druckabbauregelung mit PPC-Regelung und mit zusätzlich PWM-Steuerung eines Ventils, das die Druckversorgung DV mit Vorderachse verbindet;
• 7c: 2-kanal MUX-Regelung;
• 8a - 9b: verschiedene mögliche Modulbauweisen für das erfindungsgemäße Bremssystem, insbesondere die vorbeschriebenen Ausführungsformen;
• 10: Bremssystem für 2-Räder (ein Rad in einer Achse).

Show it:

• 1 : a first possible embodiment of a brake system according to the invention with a modular structure with a tandem master brake cylinder THZ and two-circuit fallback level in the front axle and rear axle;
• 1a : a first possible embodiment of a central brake management system for a brake system for a driver request control (FW) or an alternative control for autonomous driving (AD-Ctrl);
• 1b : Another possible embodiment of the brake system, in which the connection of the second brake circuit with the pressure supply device takes place via the piston-cylinder unit of the actuating device and the switching valve is arranged between the piston-cylinder unit and the connection of the pressure supply device;
• 1c Another possible embodiment of the brake system, in which the connection of the second brake circuit to the pressure supply device takes place via the piston-cylinder unit of the actuating device and the switching valve is arranged between the piston-cylinder unit and the pressure supply of the pressure supply device;
• 2a : a modification of the embodiment according to FIG 1 with a single master cylinder with branch circuit and master cylinder with redundant diagnosable seals, as well as a gateway circuit;
• 2 B : a modification of the embodiment according to FIG 3a , whereby only the actuation unit acts on the second brake circuit in the fallback level, and in which, in the event of a brake circuit failure, a braking torque can be achieved by the braking action of the motors on the front axle and rear axle;
• 2c : Embodiment like 3b The pressure supply is designed as an electrically driven rotary pump, for example a gear pump, with the pressure being regulated via angle sensors (position of the gear pump) and current (torque);
• 3 : fail-safe, redundant embodiment with e-pedal for recuperation and pressure control on an axis in MUX and PWM operation;
• 3a Electric axle solution with central control with individual wheel control and multiple redundancies in the braking system;
• 3b a cross-sectional view through a hydraulically assisted electromechanical brake H-EMB;
• 4th : Embodiment according to. 1c supplemented by separately operating ABS / ESP unit;
• 5 : Pressure supply with 2x3 phases and red. diagnosable seals;
• 6a , 6b : Pressure supply device with rotary pump integrated in the electric motor and HCU ;
• 7a : 2-channel pressure build-up control with PPC control and with additional PWM control of a valve that controls the pressure supply DV connects to rear axle;
• 7b : 2-channel pressure reduction control with PPC control and with additional PWM control of a valve that controls the pressure supply DV connects with front axle;
• 7c : 2-channel MUX control;
• 8a - 9b : various possible modular designs for the braking system according to the invention, in particular the embodiments described above;
• 10 : Brake system for 2 wheels (one wheel in one axle).

1 shows a first possible embodiment of a braking system according to the invention with the central control according to the invention via a central control and regulating device M-ECU _BM , the control signals to the control and regulation device S-ECU _DV1 the pressure supply unit DV1 the braking system and the control and regulation devices S-ECU _TM1 , S-ECU _TM2 the traction motors sends and from the control and regulation device S-ECU _BE the actuation unit BE Reads in driver request signals. The brake system is modular and has a separate actuation unit BE and pressure supply device DV on.

The actuator BE has a brake pedal P as well as an operating rod ST on which on a tandem master cylinder THZ acts, which in turn is carried out with a pressure piston DK and pressure piston working space AB1 and a floating piston SK and floating piston pressure working space STARTING AT 2 . There are also sensors for detecting the pedal stroke and pressure transducers DG2 and DG3 intended for redundant driver request recognition. Alternatively, in the actuation unit BE just a pressure transducer DG2 or DG3 can be used or the pressure transducer in the pressure supply can be completely dispensed with if a force-displacement sensor system KWS according to WO 2012059175A1 is used for force measurement. The pressure chambers AB1 , STARTING AT 2 of the plunger DK and the floating piston SK are for sucking up volume via sniffer hole seals SD with the storage container VB connected. The actuation unit BE is via isolation valves TV1 and TV2 from the pressure supply DV / DV1 Cut.

The pressure supply device DV consists of an electrically driven piston-cylinder unit with sensors for detecting the angular position α of the rotor and the motor current i as well as temperature T as well as one HCU with pressure transducer DG1 , Switching valves TV1 , TV2 for separating the master cylinder from the brake circuits for brake-by-wire operation and switching valves SV _A1 and SV _A2 for the individual control of the brake circuit by the pressure supply device DV . There is also a path simulator WS provided hydraulically to the pressure chamber AB1 of the plunger over the line VL ₅ is connected and via a travel simulator shut-off valve TVWS is lockable.

For regulating the brake pressure in coordination with the recuperation control via the electric motor TM2 or TM1 one axis is the PPC control method with evaluation of angular position α of the rotor of the electric motor, current i of the electric motor and optionally temperature T of the motor is used, supplemented by the evaluation of a pressure volume characteristic according to the prior art, which is preferably adapted during operation. If a temperature sensor is used, the temperature is T of the electric motor is used to adapt the relationship between current and torque of the electric motor, because the torque constant kt depends on the temperature T linearly decreased. This is used to advantage in order to realize a precise dynamic pressure change control, since the control is via the current i is more dynamic, since pressure transducers as setpoint signals have a time delay in the actual value acquisition. The pressure transmitter is primarily used for the setpoint pressure control when it comes to the exact setting of the setpoint pressure, but can also be used for the entire control. In addition, the pressure transducer is used to calibrate the pressure volume characteristic that changes during operation, for example due to air inclusions. If the pressure transducer fails, electricity is used exclusively i , the angular position α and the pressure volume characteristic are regulated, which provides additional redundancy.

The switching valves SV _A1 and SV _A2 are designed as normally closed valves to provide the pressure supply in the fallback level DV from the actuation unit BE to separate. For the simultaneous control of both axes, the multiplex method (MUX method) according to the state of the art is used 7c is described again. An additional PWM control of the Valves is not possible since in this embodiment the switching valves are designed as normally closed.

1a shows the structure of a central brake management for embodiment A and B, ie in embodiment A a brake system, for example according to 1 , whereby for regulation according to the driver's request ( FW ) via an actuation unit BE or alternatively in autonomous driving mode (AD-Ctrl) target signals AD target for brake management ( BM ) is carried out. This also includes the wheel speeds V _R1 , V _R2 , V _R3 , V _R4 and other signals (e.g. yaw moment) are taken into account. The brake management sends target torques M _target to the controls S-ECU _{TM1 / TM2} the traction motor (s) and target pressures p _should1 , p _should2 for the pressure supply to the control unit S-ECU _DV1 for the pressure supply device DV1 . The target pressures p _should1 and p _should2 are the control signals that the pressure supply device DV1 in the brake circuits BK1 and BK2 should provide for individual control of the brake circuit. In the case of driverless vehicles, the actuation unit can be dispensed with and the system is operated purely in AD-Ctrl mode.

• • achsindividuelle Druckregelung für Rekuperation (Rekuperation)
• • Bremskraftverteilung (EBV),
• • achsweises ABS für Vierräder, ABS für Zweiräder

The following functions are then preferably implemented in the central brake management of embodiment A:

• • Axis-specific pressure control for recuperation (recuperation)
• • Brake force distribution (EBV),
• • ABS for four-wheelers, ABS for two-wheelers

If embodiment B (wheel-specific regulation with one wheel brake in each brake circuit, as in the following example in 3a executed), the brake management is implemented by another S-ECU _DV2 or further brake actuators (e.g. EMB) expanded with the additional setpoint pressure signals p _should3 and p _should4 to the second pressure supply DV2 for individual control of two wheel brakes in one brake circuit each ( DV1 controls RB1 and RB2 , DV controls RB3 and RB4). If an EMB is used, instead of nominal pressures p _should3 and p _should4 Target braking torques sent as target signals. Instead of nominal pressures p _should1 , p _should2 p _should3 and p _should4 can also target braking torques M _should1 M _should2 , M _should3 and M _should4 to the S-ECU _DV1 and S-ECU _DV2 which are sent in the respective S-ECU then converted into target pressures.

Optionally, an ECU for an electric power steering ( S-ECU _EPS ) integrated into the brake management. This is used for torque vectoring or yaw moment interventions S-ECU _DV1 or. S-ECU _DV2 with the electric power steering EPS to synchronize in terms of the redundancy of the steering (emergency steering in the event of power steering failure) or improvement of agility through the simultaneous use of electric power steering and torque vectoring.

• • achsindividuelle Druckregelung für Maximierung der Rekuperation über Traktionsmotoren
• • elektronische Bremskraftverteilung (EBV)
• • radindividuelles ABS, ESP, ASR
• • Fahrzeuglenkung (Lenkungs-/ Giermomenteingriffe der Servolenkung und des Bremssystems)
• • Ansteuerung der elektrischen Parkbremse (H-EMB)

The following primary functions are then preferably implemented in the central brake management of embodiment B:

• • Axis-specific pressure control to maximize recuperation using traction motors
• • electronic brake force distribution (EBV)
• • ABS, ESP, ASR for each wheel
• • Vehicle steering (steering / yaw torque interventions of the power steering and the braking system)
• • Control of the electric parking brake (H-EMB)

The brake management can be expanded to include additional axles and additional pressure actuators for additional axles (e.g. for trucks); in addition to the above-mentioned functions, the usual functions of ABS / ESP systems and driver assistance functions can be implemented in the central brake management system or optionally in the slave ECU or AD-Crtl control can be outsourced.

1b shows the electric brake booster X-Boost of a 2-box brake system, as in WO2018233854A1 - Page 4 defined and described in the text of the patent specification. The X-Boost is used in WO2018233854A1 used with an ESP system. In contrast to the disclosure, the X-Boost is operated as a stand-alone unit without a 2nd box (ESP unit) and has two switching valves SV _A1 and SV _A2 for individual operation of the brake circuits BK1 and BK2 on. The pressure is via the pressure supply DV controlled by the forward and backward movement of the piston of the pressure supply, the pressure being controlled via a hydraulic connection via a PD1 valve and SV _A1 valve to the brake circuit BK1 and then via the PD1 valve via the floating piston K and SV ₂ valve in the brake circuit BK2 is transmitted. The switching valves are preferably designed to be normally open, so that the brake circuit-specific, simultaneous or partially simultaneous pressure curve control carried out previously via PPC control of the piston of the pressure supply DV as well as in a brake circuit supplemented by PWM control or current control of the switching valves SV _A1 and SV _A2 is or can be realized. As an alternative or in addition to PWM control, the multiplex method can also be used here.

The ECU of the X-Boost is here as a slave ECU S-ECU _DV1 or Master-ECU _BM executed. In the execution as S-ECU _DV1 the control of the X-Boost is integrated into a central control in which Executed as a master ECU _BM , the ECUs of the traction motor are controlled by the control electronics of the X-Boost TM1 or TM2 one axle or controlled by two traction motors on 2 axles. This optimally combines the recuperation control with the individual brake circuit control.

The pressure supply DV is designed as a piston pump driven by an electric motor and a spindle drive. As an alternative to the piston pump, a rotary pump can also be used. Inventive design of a rotary pump as a gear pump with HCU are in the 6a and 6b detailed.

In addition, for manufacturing reasons, it can be advantageous to split the master cylinder into two housing parts G1 and G2 split up, the first housing G1 the pressure piston of the actuation unit BE and the second housing has a floating piston K having. This enables a design as in 8a explained below.

The 1c shows a further possible embodiment of the brake system with a structure of the brake booster (X-Boost) with functionality as in FIG 1b , but with an alternative valve circuit. Here is the switching valve SV _A2 directly to the pressure supply DV connected and the pressure transmission in the brake circuit BK2 takes place via the floating piston K . The pressure transfer into the brake circuit BK1 takes place via the SV _A1 valve directly without an upstream PD1 valve. This training allows the throttle resistances between the pressure supply DV and brake circuit BK1 can be reduced and the throttle losses between pressure supply DV and BK1 and BK2 be designed approximately the same. The throttling effect between the pressure supply and the brake circuit BK2 is due to the friction of the seals on the floating piston K only slightly higher. This enables the individual control of the brake circuit in the application iV to execute the 1b be simplified. The first piston of the actuator BE is used to recognize driver requests and for the fallback level. In the fall-back level, ie if the pressure supply fails, the pressure is released via isolating valves TV1 in brake circuit BK1 headed and over TV2 and floating piston K in brake circuit BK 2 . In addition, an STB tappet is optionally provided, which is located directly on the floating piston in the fall-back level K can work.

In 1c are the two pistons of the actuation unit BE arranged in a housing. Alternatively, the piston KBE of the actuation unit BE in a first housing and the floating piston K be arranged in a second housing. A separation of the housing enables a design of the brake system that is advantageous for manufacturing reasons, as in FIG 8a detailed. In terms of the modular design, this design can sensibly be modified with the same production technology to an e-pedal solution with a separate actuation unit and pressure generator with solenoid valves.

The 2a shows a modification of the embodiment according to FIG 1 with a single master brake cylinder with T-branch circuit with two isolating valves TV1 and TV2 that establish a connection between the master cylinder and the brake circuit BK1 and / or the brake circuit BK2 can produce. The pressure control in the brake circuit BK1 and BK2 takes place via an electrically driven piston-cylinder unit in the PPC pressure control process using the angular position of the rotor, current and temperature of the electric motor and multiplex operation. This restriction makes sense because normally closed solenoid valves remove the brake circuits from the pressure supply in the event of a failure of the pressure supply and the pressure supply effectively from the actuation unit BE separate. In the event of failure, the pressure of the actuation unit takes effect BE then optionally in both brake circuits or only in one brake circuit. This decision can be made depending on the detected fault, and the availability of the traction motors on one or both axles can be used to generate additional braking torque to achieve greater deceleration or, in the event of a double fault, failure of the pressure supply and brake circuit guarantee sufficient deceleration. If the brake circuit fails, the hydraulic pressure is only fed into the brake circuit that has not failed and the respective axle where the brake circuit was detected is braked by the engine torque of the traction motor. This enables sufficient deceleration even in the event of a fault, which means that the legal requirements for the emergency braking function of approx. 0.5 g in standard vehicles are met.

To improve safety, two isolating valves connected in series can optionally be used TV1 and TV1 _R such as TV2 and TV2 _R be provided so that if the brake circuit fails, the second brake circuit is not affected and the pressure control does not act on the master cylinder.

In order to further improve reliability, instead of a tandem master cylinder, a special master cylinder with 3 redundant seals with diagnostic options is provided. The master cylinder has the seals D1 , D2 and D3 as well as connecting lines VL8 and VL9 to the storage tank VB on. Such a structure enables redundant seals on the one hand, and failure can be diagnosed on the other.

The main cylinder KZE is activated by means of a pedal tappet PS via a pressure piston DK operated, which in a known manner via a sniffer hole to the storage container VB connected. The DK Piston is in the main cylinder via various seals KZE sealed: a secondary seal D1 outwardly, a seal D2 to the printing room AR _DK and a seal D3 as a redundant seal too D2 with throttle DRS . Falls seal D3 off, a leakage current arises from the throttle DRS is limited. This leakage current is seen as a loss of volume and an extension of the pedal travel by two pedal travel sensors PS1 , PS2 recognized. The thrush DRS is dimensioned so that the pedal travel is only slightly extended during braking. The thrush DRS can also be in lines D1 and D2 to the storage container VB be used, with an additional (not shown) check valve parallel to the throttle DRS which to D1 / D2 opens towards.

The printing room AR _DK Master brake cylinder is also for the brake-by-wire functionality with a travel simulator WS connected. A check valve and another throttle DRS2 are arranged between the travel simulator and the pressure chamber. The master brake cylinder has redundant pedal travel sensors based on the KWS principle ( US 9541102 ) on. The driver's actuation force can thus be evaluated via the pedal travel and the differential travel measurement using an elastic element. If the KWS principle is not used, a pressure transmitter is required to measure the pressure in the work area AR _DK measures. This can be provided in addition to the KWS principle for redundancy purposes.

The 2 B FIG. 8 shows a modification of the embodiment according to FIG 2a , with only the actuation unit BE in the fall-back level to the second brake circuit BK2 acts and the traction motors TM1 and TM2 on one or both axes A1 , A2 also contribute to the deceleration of the wheels in the event of a fault. In addition, the master cylinder is designed differently.

The pressure control in the brake circuits is carried out in the same way as in 2a executed braking system via the pressure supply unit DV1 . Here are to safely separate the axis A1 redundant switching valves in the event of brake circuit failure SV _A1 and SV _{A1, R} provided that are normally open. In addition to the PPC and MUX control, the PWM control of the solenoid valves can also be used for pressure control. Because of the normally open design, sleeping errors can occur, eg dirt particles prevent the valves from closing. Therefore there are valves connected in series SV _A1 and SV _{A1, R} advantageous, so that a brake circuit failure BK1 on the axis A1 does not lead to a total failure of the pressure boosting. The brake circuit is also in the event of a brake circuit failure BK2 additionally via a normally closed valve SV _A2 from the brake circuit BK1 Cut. The normally closed switching valve SV _A2 is also used as a separation valve in the fall-back level in the fall-back level and separates the actuation unit from the pressure supply. This series connection is in the connection between the pressure supply and the brake circuit BK2 not required as a normally closed valve SV _A2 is used, which is not prone to sleeping errors.

The master cylinder has as in 2 redundant diagnosable seals and differs from the variant in 2 in that a path simulator shut-off valve WHAT as well as a pressure transducer for pressure measurement in the pressure chamber AR _DK is provided for recording driver requests. The actuating force can be redundant via the pressure transmitter and KWS are recorded. The travel simulator shut-off valve WHAT is used to reduce idle travel in the event of a failure of the pressure supply and to feed the pressure of the actuation unit into the brake circuit via the isolating valve BK2 used. The travel simulator shut-off valve can also be dispensed with if the travel simulator is designed accordingly and an idle travel is accepted.

The 2c shows a further possible embodiment with the same hydraulic concept as in FIG 2 B with the difference that the pressure supply is an electrically driven rotary pump, for example a gear pump according to the explanations in 7a and 7b is designed, with the regulation of the pressure via angle sensors (position of the gear pump via rotor position of the motor) and motor phase current for estimating the motor torque and the pressure. The gear pump can be used like a piston-cylinder unit for pressure build-up and pressure reduction. To reduce the pressure, the direction of rotation of the motor of the gear pump is simply changed. In addition, the PPC and MUX control can be used and, thanks to PWM control of the solenoid valves, a further degree of freedom in the pressure curve control with normally open valves between the pressure supply and the brake circuit BK1 be achieved. In contrast to the pressure supply as a piston-cylinder unit, a leakage of a gear pump in the pressure control must be taken into account in the control. Therefore, when the target pressure is reached, the pressure is preferably set by closing the switching valves SV _A1 and or SV _A2 held.

The 3 shows a pure brake-by-wire solution without a hydraulic connection between the actuation unit BE and brake circuit with an electric pedal. A central one M-ECU _BM reads in the signals from the electric pedal and sends target signals to the control and regulation device S-ECU _DV1 the pressure supply unit DV1 . Redundant signal lines are used for signal transmission DS1 and DS2 used. The redundant data transmissions can be wired or wireless in the future (e.g. with data transmission options with low latency, e.g. 5G Data transfer or Bluetooth protocols). The pressure supply DV as well as the connection to the brake circuits is provided with multiple redundancies, as in 5 detailed, the brake circuits with the pressure supply via two series-connected normally open solenoid valves SV _A1 , SV _{A1, R} for brake circuit BK2 such as SV _A2 and SV _{A2, R} for brake circuit BK1 can be locked or separated so that dormant faults in one brake circuit cannot affect the second brake circuit. Since the valves have no blocking function with respect to the actuation unit BE must map, these can be designed to be de-energized-open and thus enable all degrees of freedom in the individual control of the brake circuit (PPC control, PPC + PMW control, PPC + MUX control) and can very effectively apply the braking torque of one or more traction motors TM1 , TM2 be voted on.

The 3a shows embodiment B of the brake system according to the invention, with a brake system being provided as a module for an electric axle and the two brake circuits of the brake system being the wheel brakes RB1 and RB2 one axis A2 serve. Switching valves are connected in series between the pressure supply and the wheel brakes SV _A1 and SV _{A1, R} or. SV _A2 and SV _{A2, R} provided so that the failure of one brake circuit, as described above, does not affect the pressure supply and leads to the failure of the second brake circuit. There is a traction motor on axis 2 TM1 or two electric traction motors TM1 / TM2 provided, wherein the traction motor (s) can drive the axle or wheels directly. This embodiment is chosen, for example, for a rear axle, where the electric traction motors can better transfer their effect to the road because of the weight distribution during acceleration, especially in powerful vehicles.

As an alternative or in addition to the traction motors TM1 / TM2 can on the axis A2 electric power steering can also be used. This is useful, for example, when the axis A2 the front axle of a motor vehicle is where the electric power steering is typically located.

The pressure control takes place in PPC , MUX or PPC with PWM control / current regulation of the normally open switching valves. The braking torques can be increased by the electric motors in the sense of high braking force dynamics or in the sense of further redundancies. In addition, ABS / ESP control on an axle as well as torque vectoring and steering functions can be implemented through the various possible embodiments. In addition, the pressure supply is redundant in several ways. There are redundant seals that can be diagnosed, as well as redundant sensors for angular position, temperature and current, and a redundant on-board network connection. If a ball screw drive is used as a gear, the entry of dirt particles into the ball track can cause the spindle to block. Appropriate quality measures must be taken to prevent this. Alternatively, a trapezoidal spindle without balls can be used with the disadvantage of poorer efficiency and lower load. It is also conceivable that an electrically driven rotary pump is used instead of the electrically driven piston pump.

In embodiment B with the central brake control M-ECU _BM a further brake system or an actuator for generating braking force for a further axis (axis 1) is preferably provided. This can be an identical module to the one that supplies axis 2 or, alternatively, it can be an electromechanical brake EMB or an electromechanical brake (H-EMB) that is hydraulically assisted via a pressure supply, which in the exemplary embodiment in 3b is described in more detail. Axis 2 can also be designed like the module for axis 1. Each axis can be configured individually and also contain parts of the axis solutions shown (e.g. no redundancies in pressure supply and valves connected in series) and can be supplemented by electric power steering on one or both axes. The corresponding solution is driven by safety requirements according to the levels of automated driving and the vehicle type.

The H-EMB comes with a pressure supply DV2 connected to a switching valve. The pressure can be maintained with the switching valve or a second H-EMB can be connected. Both H-EMB are operated in MUX mode or in PPC mode with optional PWM control / current regulation of the solenoid valves and can alternatively or simultaneously generate a braking torque hydraulically and electrically using the electric motor of the H-EMB. In addition, the parking brake can be mapped by the H-EMB module, for example by a gearbox with self-locking and thus also a redundancy of the individual wheel control can be generated by hydraulic or electrical actuation of the H-EMB.

In an H-EMB version, the pressure supply can be significantly simplified compared to axis 2, since an electric motor of the H-EMB module is also available to generate the braking force. The piston pump (piston-cylinder unit) can be provided with a plastic housing and / or an inexpensive trapezoidal spindle can be used. The torque of the The drive motor can also be dimensioned very small. Here, too, the use of an inexpensive electric rotary pump as a pressure supply is possible and advantageous.

Such a solution is predestined for an e-pedal solution with redundant data lines DS1 and DS2 . The pressure supply (s) DV1 , DV2 serves or serve as a slave, which has a control and regulation unit M-ECU _BM is or are controlled. This allows all degrees of freedom of the driving dynamics (ABS / ESP control, braking force generation, recuperation via traction motors, steering interventions via brakes and / or electric power steering, torque vectoring via brakes or traction motors) to be controlled; at the same time, all functions with power restrictions are available redundantly.

3b shows a cross-sectional view through a hydraulically assisted electromechanical brake H-EMB, which is connected to the pressure supply device via a hydraulic connection HL DV2 can be connected, so that a force can be applied to the brake disks either via the hydraulic system and / or the electric motor EM. The rotary movement of the electric motor is here transferred into a linear movement via a gear G and generates the force F _EM on the wheel brake. The transmission G is preferably designed to be self-locking, so that the parking brake works safely when the on-board power supply fails. In addition to the electric motor, a hydraulic force F _{hyd is} generated via the pressure _supply . Depending on the version of the EM as a brush motor or brushless motor with lower or higher power, the dynamics of the braking torque change and the additionally available braking torque can be determined by the H-EMB through the appropriate design of the components and matched to the hydraulic brake.

The pressure supply device DV2 is an alternative to the piston pump ( 3a) here as an electrically driven rotary piston pump RP executed. The rotary piston pump RP is advantageously structured as in 6a and 6b executed.

In addition to actuating the brake, it is possible to actuate a clutch via a KMV _K1 solenoid valve with the pressure supply or 2 clutches via two solenoid valves or separate hydraulic lines. Two clutches K1 , K2 are intended, for example, for a two-speed transmission with power shift capability for a TM3 electric motor. To reduce the pressure in the clutch, solenoid valves are also provided, which are connected to a reservoir for pressure reduction and are typically designed as proportional valves or switching valves. PWM mode is typically used for pressure reduction. In this case, axle 1 is typically the rear axle of a motor vehicle. The brake and clutch are preferably operated in MUX mode, since gears are not shifted at the same time. In addition, the PPC process and PPC process with PWM / current control of the solenoid valves can also be used here as a further degree of freedom. If different hydraulic media are required to operate the H-EMB and the clutches, appropriate media separation must be provided. The pressure is then transmitted to the clutch, for example via a media separating piston and the clutch system K1 and K2 is provided with a separate reservoir from which hydraulic fluid is drawn and returned. System separation options, such as in WO10037519_A2 executed, or use of storage chambers possible. The 3a therefore only shows the basic control of H-EMB and coupling and may have to be expanded for safety reasons / media separation requirements.

The 4th shows an embodiment with a brake booster (X-Boost) according to. 1c , supplemented by a separately operating ABS / ESP unit which is connected to the output line VL _b1 and VL _b2 . The ABS / ESP unit takes over the individual wheel control of brake pressures in ABS / ESP driving dynamics interventions, the brake booster (X-Boost) the brake booster and the blending function. The EBV control or axis-by-axis ABS can be implemented in both units.

The X-Boost largely corresponds to the structure of the 1b and differs from this only in two respects. No actuation tappet STB is provided, which creates a mechanical connection between the pressure piston / brake pedal and the floating piston and thus ensures that the driver can access the other brake circuit if one brake circuit fails. This is permissible for many applications due to the redundancy of the pressure supplies. In addition, check valves RV1 and RV2 are provided to ensure that fluid is sucked in quickly from the ABS unit's reservoir if the X-Boost fails. This addition is highly recommended for a 2-box brake system solution. casing G1 and G2 are separate and thus enable an advantageous design as shown in 8a .

In this embodiment too, the components of the braking force system and the electric motors are controlled centrally via a control and regulating device M-ECU _BM controlled and also the control and regulation device S-ECU _{ESP / ABS} is in integrated into the control, e.g. for appropriate valve actuation of the solenoid valves of the ABS / ESP unit for the axle-specific recuperation control, which is primarily via the M-ECU _BM is controlled. So are the valves SV _A1 and SV _A2 Preferably used in recuperation mode, but alternatively the ABS / ESP unit solenoid valves can also be used via the M-ECU _BM Receive setpoint control signals if access to the S-ECU _{ABS / ESP is} possible. This is the less preferred solution, since the ABS / ESP units usually have closed system architectures from Tier 1 manufacturers and access is only possible in close cooperation with an ABS / ESP manufacturer and the signal transmission is also subject to errors. Therefore, in terms of a simple structure, functions of the axle-specific brake force control and recuperation are the primary master function of the X-Boost and control functions for ABS / ESP operation are the primary function of the ABS / ESP unit.

The 5 shows a redundant pressure supply in the form of an electrically driven piston-cylinder unit with 2x3 phases and redundant diagnosable seals. The pressure supply device DV1 has two control and regulating devices DV-ECU1 and DV-ECU2. The pressure supply device also has an electric motor M1 on, the rotor R of which adjusts a spindle SP which is connected to a piston KB. By adjusting the piston KB, a pressure can be built up in the pressure chamber DR, which can be passed into a brake circuit BK via the isolating valve TV. The piston is sealed by several redundant seals in the cylinder, as with the actuation unit BE a redundant, diagnosable sealing system is created. In the case of the pressure supply device, too, a hydraulic line leads to the reservoir between the seals. This means that the pressure supply is still fully operational and redundant even if a seal fails. The detection of the failure of seals is carried out analogously to the redundant master brake cylinder according to 2a . The pressure chamber DR is connected to the storage container via a check valve. Thus, the pressure supply can deliver and thus deliver continuously with short interruptions. Each of the two control and regulating devices DV-ECU1 and DV-ECU2 are via 1x3 phase lines with separate winding or phase systems of the motor M1 in connection, so that if a control and regulation device or a winding system fails, the motor M1 can still be operated via the other winding or phase system and the other control and regulating device, even if then only about half the torque by means of the drive M1 can be generated. One or both control and regulating device (s) has or have sensors for determining the temperature T , the motor current i and the rotor angle of the electric motor α. The measurement data from the sensors are used for precise PPC pressure control or for operation in the event of a pressure transmitter failure. To achieve a high level of availability, not only are the control and regulating devices DV-ECU redundant, but also power supplies BN1, BN2 and data and control lines DS1 and DS2 provided twice. The power supplies BN1 and BN2 can, for example, be different voltage levels of an on-board network or separate on-board networks.

The 6th and 6a show possible designs of the pressure supply with a rotary pump. The 6th shows a representation of the entire unit consisting of the motor 22nd , Pump Z, HCU and ECU which is capable of exercising pressure regulation and control for brake systems. The main focus here is on the combination of motor and pump. In the bearing flange 18th the pump is arranged or in a separate pump housing 40 as shown in the upper half of the picture HCU or ECU attached. The HCU includes solenoid valves and pressure transducers required for the particular solution. So are in execution after 3c and 3b the solenoid valves and pressure transducers DG in the HCU integrated. The HCU can also contain hydraulic components and sensors for actuation of clutches (solenoid valves, pressure transducers). As usual, the motor consists of a rotor 21st , which over the driver 10a is connected to shaft 1. The rotor 21st is via a permanent magnet in the housing 30th axially preloaded by its force. This is a solution for the motor manufacturer, which motor with housing 22nd and stator and winding 23 manufactures, tests and delivers to the system supplier. Here the motor is tested without a pump with an auxiliary shaft. Thereafter, when the shaft is removed, the rotor is centered by the axial magnetic force, so that the shaft 1 can then be assembled with the rotor during final assembly. The drive housing must also be connected to the flange 18th at 25a - shown in the lower half of the picture - are assembled and attached, e.g. B. with springs, which are attached in segments over three connections. There is also a housing seal here 31 necessary. The fastening can be done by caulking, at 25 of the motor flange with HCU or ECU, see upper half of the picture 28 , respectively. The pump version with pump housing is shown here. The motor is shown here as a brushless motor that needs a motor sensor for commutation and control of the volume delivery of the pump. This motor sensor is remote from the drive housing 22nd arranged, with a sensor shaft 26th , which is arranged or attached to the drive shaft 1, a sensor target 27 wearing. This target 27 acts on the sensor element 28 , which is on the circuit board of the ECU is arranged. The winding is via contact bars 24 connected to the ECU.

The motor with a bearing flange 18th can be connected directly to the hydraulic housing HCU , which contains valves or other hydraulic components, are connected to the pump. If this is not the case, the drive housing can be connected 22nd , 18th directly to the housing of the ECU.

It is also possible to have the gear pump Z in a pump housing 40 to arrange which directly with hydraulic housing HCU connected as it is in 5 is shown in the upper half of the drive shaft 1. Before assembling the pump housing 40 and hydraulic housing HCU or pump housing 40 and ECU is first the gear pump Z in the pump housing 40 integrated or mounted, then the rotor 21st pressed onto the shaft 1 and then with the bearing 20th is assembled. Here the pulling force of the magnet 30th additionally on the rotor 21st and the camp 20th act, making the bearing look like a four-point bearing. So that is the motor housing 22nd with the gear pump Z and its pump housing 40 and can be connected to the hydraulic housing in the next step HCU or the electronics housing ECU. This is done using the fastening screw 41 used. The shaft 1 is previously in the outer discs 7.1 and 7.2 centered so that the pump housing 40 before screwing it to the hydraulic housing HCU or the electronics housing ECU is centered with shaft 1.

The pressure supply device according to 6a uses a 2-stage pump with long plain or roller bearings accordingly 2 and 4th which does not require separate engine storage. Accordingly, the motor structure with the housing is simplified. The rotor 21st sits with driver 10a on the motor shaft and is axially connected to the locking ring. The pump housing protrudes slightly into the here HCU inside.

The 7a shows a pressure build-up control with PPC control and with additional PWM control of a solenoid valve that connects the pressure supply with the hydraulic consumer, here for the rear axle and front axle.

The pressure build-up on the front axle takes place through precise pre-pressure control using the PPC process with a pressure signal as a control variable or the use of electricity i , Temperature T and angular position α. The solenoid valve is constantly open here. Here pressure, the pre-pressure can be regulated very precisely over time and the pressure p _VA the front axle. The precise pressure regulation and the pressure curve over time are particularly important for a very precise coordination with the braking torque of the electric traction motor TM. At the same time, the rear axle is _{excited in} the pressure _curve via the pre-pressure of the pressure _supply p _DV1 and the opening cross-section of the solenoid valve via PWM control or current regulation of the ball seat valve. The different pressure curves are used to simultaneously vary the pressure curves on the axles (EBV function) or to optimally regulate the recuperation of a traction motor on one axle or recuperation with 2 traction motors on 2 axles that generate different braking torques.

The 7b shows a pressure reduction control with PPC control and with additional PWM control of a valve that supplies the pressure DV1 connects with VA. The pressure reduction regulation follows the same logic as the pressure build-up regulation in 7a with the difference that the axis, which is operated with a higher pressure, requires a smaller opening cross-section. In this case, the solenoid valve on the front axle is PWM-regulated or current-regulated.

The 7c again shows a multiplex control (MUX control) with which the brake pressure in the two brake circuits can alternate individually, that is, one after the other in small steps or can also be changed simultaneously. Here the pressure is regulated one after the other, which leads to a time delay ΔtMux, which, however, is so small that there is little or no restriction of the function. In order not to make this noticeable for the driver, the pressure regulation must either be carried out very quickly one after the other or the torque regulation of the traction motors adapted. Alternatively, as is known from the prior art, the MUX control can also take place simultaneously or partially simultaneously. This leads to somewhat higher noises, which in driving operating states, where this is necessary, with a delay of 1g, is however regarded as uncritical.

The 8a to 9b show various possible modular designs, ie arrangements of the individual components of the brake system according to the invention with respect to one another for different designs of the brake system.

The 8a shows a first possible embodiment of the braking system according to the invention as a module or structural unit MO , the valve unit HCU and the operating unit BE in separate housings G _HCU and G _BE are arranged, which are either adjacent or as in 8b shown, are arranged separately from each other. The motor axis of the drive of the pressure supply device or, if available, axis A of the piston-cylinder unit of the pressure supply DV is parallel to the axis of the piston-cylinder unit of the actuating unit BE aligned. This construction can in particular for the embodiments of the brake system according to the 1b and 4th can be used. The valve arrangement HCU can all solenoid valves, pressure transducers DG and / or pistons, in particular floating pistons, of the pressure supply DV include. The path simulator WS can either entirely or partially in the housing G _BE the actuation unit BE or the housing G _HCU the valve assembly HCU be. This structure is in view of a very cost-effective manufacturing method of the hydraulic block of the valve arrangement HCU makes sense, whereby the manufacturing process can use the extrusion technology of modern ESP / ABS systems.

By arranging the valve arrangement and the actuating unit in separate housings, the actuating unit can be removed from the module or the structural unit and can be separated from it.

The 8b shows the arrangement according to FIG 8a , however, the brake system has an electric pedal, which is part of the of the unit or the module MO separately arranged actuation unit BE is. The actuation unit BE is via data and signal lines DS1 , DS2 with the module MO in connection. There is no hydraulic connection.

The 9a and 9b show similar modules or units MO like them in the 8a and 8b are shown and described, with the difference that the pressure supply DV a rotary pump instead of a piston-cylinder unit ZRP having. In the embodiment of 9a is the axis of the motor driving the rotary pump transversely to the axis of the piston-cylinder unit of the actuating device BE aligned or arranged. The braking system can according to the 2c be trained. The training of the rotary pump ZRP can like in the 6a or 6b can be selected. The hydraulics, as in 3 be designed as described. This then leads to the structural unit 10b with separate electric pedal.

The 10 shows the braking system for a two-wheeled vehicle in which the vehicle has only one wheel per axle. The wheel brakes RB1 and RB2 are each a brake circuit BK1 and BK2 assigned, which by means of the pressure pressure supply unit DV1 , preferably in the form of an inexpensive rotary pump, via the switching valves SV _A1 and SV _A2 are supplied. Otherwise the structure of the braking system corresponds to that of 1 . Alternatively and preferably, two-wheelers, in particular less powerfully motorized e-scooters or electric pedelecs with lower top speeds that are in 2c executed more cost-effective hydraulic circuit with fewer valves and actuation unit with a single-circuit feed via the actuation unit BE be carried out in the front brake, the rear wheel being driven and decelerated by only one electric traction motor.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• WO 2018215397 A1 [0002]
• EP 1874602 B1 [0003]
• DE 102005055751 B3 [0003, 0004]
• DE 102005018649 B3 [0003, 0005]
• DE 102005063659 B3 [0003, 0006]
• EP 1907253 B1 [0003, 0007, 0015]
• DE 102013224313 A1 [0021]
• US 9981645 B2 [0021]
• WO 2018/130406 [0021]
• WO 2012059175 A1 [0026]
• WO 2018233854 A1 [0036]
• US 9541102 [0046]
• WO 10037519 A2 [0061]

Claims (28)

Braking device for a motor vehicle with two axles (A1, A2), at least one axle (A1, A2) having an electric traction motor (TM) for driving and braking the at least one wheel arranged on the axle (A1, A2), and energy can be recovered by means of the traction motor (TM) during braking, - each wheel has a wheel brake (RB1, RB2, RB3, RB4; H-EMB _i ; EMB _i ), - a pressure supply (DV) with one of an electric motor (M ) driven pump (P), in the form of a piston-cylinder unit or a rotary pump (ZRP), - the pressure supply (DV) can both build up pressure and decrease pressure, in particular by moving the piston back and forth Cylinder unit or reversing the direction of rotation of the rotary pump, and at least one pressure supply outlet (DVa), - the pressure supply (DV) is part of a pressure supply device (DV1), the pressure supply device (DV1) having at least two output lines (VL _a1 , VL _a2 ) and at least two connections (VL _b1 , VL _b2 ) for connection either to the brake circuits (BK1, BK2), an ABS / ESP unit (ABS / ESP) and / or an actuation unit (BE) , and - each connection (VL _b1 , VL _b2 ) can be separated from the pressure supply (DV) by means of at least one switching valve (SV _A1 , SV _A2 ), - each output line (VL _a1 , VL _a2 ) with the pressure supply output (DVa) directly or is hydraulically connected via a connecting line (VLd), - a control and regulating device (ECU) controls the at least one electric traction motor (TM) and the components of the pressure supply device (DV1) in such a way that the pressure supply device (DV1, DV2) and the at least one electric traction motor (TM1, TM2, TM3) for each brake circuit (BK1, BK2), each axle (A1, A2) or the wheel brakes of an axle (A1, A2) individually, i.e. with different braking torques on the respective axles (A1, A2) or wheel brakes r axis (A1, A2), a braking delay can be adjusted. Braking device according to Claim 1 , characterized in that an actuation device (BE) with a brake pedal (P), in particular in the form of a hydraulic actuation unit with a travel simulator (WS) or an electric pedal (EP), is provided. Braking device according to Claim 1 or 2 , characterized in that the braking force on the axles (A1, A2) is generated in the interaction of the pressure of the pressure supply device (DV1) and / or the actuating unit (BE) with the braking torque of the at least one electric traction motor (TM), the control and control device (ECU _BM ) controls the components in such a way that the braking deceleration at low vehicle speeds (<120 km / h) is preferably exclusively or largely (> 2/3 of the deceleration) by means of the electric traction motor (TM), in such a way that as much as possible kinetic energy of the vehicle can be converted into electrical energy and stored. Braking device according to one of the Claims 1 to 3 , characterized in that one or two control and regulating device (s) (S-ECU _DV1 , S-ECU _DV2 ) for the pressure supply device (s) (DV1, DV2) and / or at least one control and regulating device (S-ECU _TM1 , S-ECU _TM1 ) is or are provided for at least one traction motor (TM1, TM2) which communicates bidirectionally with a higher-level control and regulating device (S-ECU _BM ) and / or communicate with one another. Braking device according to Claim 4 , characterized in that a redundant bidirectional signal transmission between master ECU (M-ECU _BM ) and slave ECUs (S-ECU _DV , S-ECU _TM ) is provided for communication between the control devices, either wired or in the form of a wireless or a combination of wired and wireless, preferably redundant, radio data transmission with short latency times (for example 5G radio transmission, Bluetooth data transmission). Braking device according to one of the Claims 1 to 5 , characterized in that the actuating device (BE) has a piston-cylinder unit (KZE) with two pistons (auxiliary piston KBE and floating piston K), the auxiliary piston of which is adjustable via a brake pedal (P) and one Working space, which is hydraulically connected to a travel simulator and whose floating piston (K) separates two pressure spaces (AR1, AR2) in a sealing manner, the second output (VL _b2 ) via a connecting line (VL _a2 ) to the one second pressure space (AR2) is in hydraulic connection, and the first pressure chamber (AR1) is hydraulically connected to a hydraulic connection line (VL _{a2 '} ) with the pressure supply (DV) and with a first outlet (VL _b1 ), wherein in one of the, preferably two connection lines ( VL _a2 , VL _a1 ) a switching valve (SV _A1 , SV _A2 ) is arranged. Braking device according to one of the Claims 1 to 5 , characterized in that the actuating device (BE) has a piston-cylinder unit (KZE) with two pistons (auxiliary piston KBE and floating piston K), the auxiliary piston of which is adjustable via a brake pedal (P) and delimits a working space which is hydraulically connected to a Path simulator is connected and the floating piston (K) separates two pressure chambers (AR1, AR2) sealingly, the second output (VL _b2 ) via a connecting line (VL _a2 ) with a second pressure chamber (AR2) is in hydraulic connection, and the first pressure chamber (AR1) with a hydraulic connecting line (VL _{a2 '} ) is hydraulically connected to the pressure supply (DV) and with a first output (VL _b1 ), the first output VL _b1 via a switching valve (SV _A1 ) and the second Output VL _{B2 can be} hydraulically separated from the pressure supply (DV) via a switching valve (SV _A2 ). Braking device according to Claim 6 or 7th , characterized in that a first housing G1 for the auxiliary piston with travel simulator and a second housing G2 for the floating piston, solenoid valves SV _A1 , SV _A2 , FV, PD1, TV1, TV2) is provided Braking device according to one of the preceding claims, characterized in that a normally closed, isolating valve (PD1) or two normally closed valves (SV _A1 , SV _A2 ) is interposed between the output lines (VL _A1 , VL _A2 ) and the pressure supply (DV) ., so that if the pressure supply fails, pressure is only fed into the brake circuits by actuating the actuating device (BE). Braking device according to one of the preceding claims, characterized in that a pressure transmitter (DG1, P / U), preferably the pressure transmitter at the output (DVa) of the pressure supply device (DV1) for determining the pressure in an output line (VLa1, VLa2) for calibrating the PPC Pressure control (pressure control via current, piston travel and pressure-volume characteristic) is provided for the purpose of highly dynamic and precise pressure control and / or pressure control operation in the event of failure of at least one pressure transducer. Braking device according to one of the preceding claims, characterized in that the actuating device (BE) has a piston-cylinder system (KZE) with only one piston (DK) and one pressure chamber (AR _DK ) and has an output line VL _b4 , which with one brake circuit (BK1, BK2) each is connected and each brake circuit can be hydraulically separated via two separating valves (TV1, TV1, R; TV2, TV2, R) arranged in series. Braking device according to one of the preceding claims, characterized in that an ABS / ESP unit is interposed between the pressure supply device (DV1) and the brake circuits (BK1, BK2), the ABS / ESP unit with its inputs to the connections (VL _b1 , VL _b2 ) is connected. Braking device according to one of the preceding claims, characterized in that the pressure supply device (DV1) has two further connections (VL _b4 , VL _b5 ) which are used to connect to the actuation device (BE) and, through pressure build-up by the pressure supply device, diagnosis of the actuation unit, in particular in the event of a failure of the seals of the piston of the actuating unit BE. Braking device according to one of the preceding claims, characterized in that the pressure supply device has either a piston pump driven by an electric motor and a non-hydraulic transmission device or a rotary pump (RP) driven by a, in particular an electric motor, a regulated volume control by means of the rotary pump (RP) can be carried out for both pressure build-up and pressure reduction. Braking device according to Claim 14 , characterized in that the rotary pump is a gear pump (ZRP) and is single-stage or multi-stage, with several stages being arranged hydraulically in series. Braking device according to one of the preceding claims, characterized in that an axle (A1, A2) has one or two wheels. Braking device according to one of the preceding claims, characterized in that the pressure supply device (DV1) is divided into at least two modules (G _HCU , G _BE ) or has at least two housings (G _HCU , G _BE ), in which one module (G _HCU ) solenoid valves (SV _A1 , SV _A2 , BP1), pressure transducers (DG1, P / U) and, if available, check valves (CV1) and hydraulic components of the pressure supply (DV) are arranged. Braking device according to one of the preceding claims, characterized in that the actuating device (BE) is arranged in a separate module or housing (G _BE ), wherein either the actuating unit (BE) positively and / or non-positively and / or by means of connecting elements with the Housing (G _HCU ) is hydraulically connected and / or arranged remotely from the housing (G _HCU ) and is connected to the module (G _HCU ) via signal and / or hydraulic lines. Braking device according to one of the preceding claims, characterized in that at least the pressure supply (DV), the at least one control and regulating device, the valve arrangement (HCU) and the reservoir (VB) are combined to form a structural unit or a module, with either in the Assembly or the module with the actuating device (BE) or this is arranged in a separate housing on it or at a distance and is connected to the assembly or the module or its components via data lines (DS1, DS2) and / or hydraulic lines. Braking device according to one of the preceding claims, characterized in that two isolating valves (TV1, TV2) are provided, the inputs (TV1e, TV2e) of which are connected to one another via a connecting line (VL ₁₀ ), the actuating device (BE) only having one working space (AR ) and a piston (K), the working space (AR) being connected to the connecting line (VL10) via a hydraulic connecting line (VL4), and the outlet (TV _1a , TV _2a ) of a separating valve (TV1, TV2) is in connection with a brake circuit (BK1, BK2) via a hydraulic line. Braking device according to one of the preceding claims, characterized in that the piston-cylinder unit (KZE) is designed as a simple master brake cylinder (HZ) with an actuating unit (BE) and has three seals (D1, D2, D3) arranged next to one another in the axial direction, between each two seals (D1, D2; D2, D3) a channel (VL8, VL9) opens into the piston-cylinder unit (KZE), in particular its working space (AR), the channels with the storage container (VB) are in connection and a throttle (DR) is arranged in a connecting line (VL8). Braking device according to Claim 21 , characterized in that the functionality of the seals is diagnosed by measuring the leakage flow through one or both connecting lines (VL8, VL9). Braking device according to one of the preceding claims, characterized in that the gear pump (ZRP) is arranged or integrated in the motor housing of the motor driving it, in particular at least partially within its rotor of the driving motor. Braking device according to one of the preceding claims, characterized in that the rotary pump (ZRP), its drive and valves and pressure transducer (DG) are combined or arranged in a structural unit, a module or a housing. Braking device according to one of the preceding claims, characterized in that the drive or rotor of the drive of the rotary pump runs dry or is sealingly separated from the hydraulic medium of the rotary pump to be conveyed, in particular by means of at least one seal from the parts of the rotary pump conveying hydraulic medium. Braking device according to one of the preceding claims, characterized in that one pressure supply device (DV1, DV2) controls or adjusts the pressure in the wheel brakes of an axle (DV1 for RB1, RB2; DV2 for RB3, RB4), with each brake circuit (BK1 , BK2) is intended for two wheel brakes. Braking device according to one of the preceding claims, characterized in that a hydraulic-electromechanical brake (H-EMB) is arranged on an axle (A1, A2), in particular on each wheel of an axle, the hydraulic-electromechanical brake (H-EMB ) is supplied with or controlled by hydraulic pressure via the pressure supply device (DV1, DV2), in particular the hydraulic-electromechanical brake (H-EMB) for the parking function applies at least part of the braking torque required for this or the entire braking torque. Braking device according to one of the preceding claims, characterized in that the pressure supply device (DV1, DV2) of an axle is additionally provided for the adjustment of hydraulic actuators, two clutches (K1, K2) of a load interruption-free two-speed transmission, the two-speed transmission having the torque of a traction motor (TM1, TM2) of an axle (A1, A2) transfers to the wheels.

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