IP Portfolio A1 –
IBS Basic

Overview

IBS Basic — Core innovations for the electrohydraulic sequential brake booster

Portfolio A1 comprises the core innovations for the IBS Basic electrohydraulic sequential brake booster — an electrohydraulic braking system without a travel simulator. The innovations were developed between 2005 and 2010 and launched on the market as series products starting in 2013.

The portfolio contains 4 patent families with 19 patents and a total of 23 core inventions or independent claims in 5 jurisdictions (DE, EP, FR, GB, US). The foundational E87 family — with 624 forward citations from 50 patent applicants — establishes the basic principle of piston pressure control (PPC) and sequential MUX valve control that underlies all modern integrated brake systems.

Four patents from Portfolio A1 were brought before the Federal Court of Justice (BGH). In each case, the BGH reversed the first-instance decision of the Federal Patent Court and upheld the IPGATE patents — a historically unprecedented clean sweep across four consecutive BGH proceedings.

Patent Families

Four patent families · 23 core innovations

Each family addresses a distinct functional layer of the IBS Basic architecture, from foundational pressure control through fail-safe accumulator design.

PPC · MUX

Patent Family E87

MUX Pressure Control / Piston Pressure Control (PPC)

April 21, 2005

The foundational patent for electrohydraulic brake-by-wire. Current-proportional pressure control, adaptive map-based piston position, sequential MUX valve control, and AEB. 624 forward citations from 50 applicants. BGH final legal validity (X ZR 111/22).

12 Core Innovations

See Patent Family

Brake Booster

Patent Family E112

Electric Motor Brake Booster — Differential Travel Control

February 3, 2009

Protects the core function of IBS Basic: the electric motor-driven follow-up brake booster with differential travel control. Over 100 million units produced worldwide. Three BGH victories (X ZR 91/23, X ZR 134/23, X ZR 133/23).

3 Core Innovations

See Patent Family

Regenerative

Patent Family E117

Regenerative Accumulator-Buffered EHB Brake Booster

September 30, 2009

Braking system for hybrid vehicles with a multifunctional storage device used for both ABS pressure relief and regenerative blending. Provides controlled pedal force feedback during generator braking. Upheld by the Federal Patent Court (Jan 31, 2024); appeal pending before BGH.

4 Core Innovations

See Patent Family

Fail-Safe

Patent Family E120

Fail-Safe Storage Chamber Pressure Relief

June 2, 2010

Uses the existing spring-loaded ABS/ESP reservoir as a hydraulic emergency buffer in the event of a blocked drive or transmission. Prevents brake lock-up without additional components or external power. 6 patents in 4 jurisdictions (DE, FR, GB, US).

4 Core Innovations

See Patent Family

At a Glance

Patent Family Summary

Glossary

Nomenclature

The following nomenclature is based on the technical publications of IBS Technology (Brake Manual, 5th edition; IBS Technology, Leiber/van Zanten 2025) and is used consistently in all portfolio documents.

IBS

Integrated Brake System — umbrella term for the integrated brake system platform.

IBS Basic

Electrohydraulic Sequential Brake Booster with Differential Travel Control (Measurement Principle A2) — subject of Portfolio A1.

IBS Premium

Electrohydraulic brake-by-wire system with pedal feel simulator (Measurement Principle B2) — subject of Portfolio A2.

PPC

Piston Pressure Control — core method of electrohydraulic pressure control via piston position and motor current.

MUX

Hydraulic Multiplexer — sequential ABS pressure control in a closed brake circuit.

HDS / HPC

Highly Dynamic Pressure Control — cascaded control architecture with plunger flow control and valve modulation.

F-BbW

Fail-Safe Brake-by-Wire — BbW system with a mechanical fallback in the event of a power failure.

THZ / TMC

Tandem Master Cylinder.

TTL

Time to Locking Pressure — time to reach wheel locking pressure (100 bar).

AEB

Automatic Emergency Braking.

NVH

Noise, Vibration & Harshness.

DAG

Double Air Gap — motor type with increased dynamics for MUX operation.

References

References & Further Reading

The technical fundamentals of the innovations documented in this portfolio are described in greater detail in the following publications.

1. [1]Feigel, H.-J.; Zimmermann, J.; van Zanten, A.; Leiber, H.; Leiber, T.; Köglsperger, C.; Unterfrauner, V.: "Integrated Braking Systems," Chapter 20, in: Breuer, B.; Bill, K.H. (eds.): Brake Handbook, 5th edition, Springer Fachmedien, 2017.First comprehensive technical publication on the IBS system concept in the standard reference work on brake technology.
2. [2]Leiber, T.; van Zanten, A.: "IBS Technology," IPGATE AG Technical Paper, March 2025 (https://ipgate.ch/ibs-technology/).Current technical overview of the IBS platform, including a description of the PPC method, the A1/A2/B1/B2 measurement principles, MUX control, the blending method, and AEB functionality.
3. [3]Leiber, T.; Köglsperger, C.; Unterfrauner, V.: "Modular Braking System with Integrated Functions," ATZ 2011-06, pp. 466–472.First publication of the IBS concept and brake management.
4. [4]Leiber, T.; Leiber, H.; van Zanten, A.: "Electromechanical Brake Booster for Automated Driving," ATZ 03/2019, pp. 50–54.Presentation of the fail-operational requirements for SAE Levels 3–5.
5. [5]Leiber, T.; Köglsperger, C.; Hecker, C.: Presentation at the VDI Knowledge Forum, October 25, 2017.In-depth description of the fail-safe architecture and the BLS method for reducing residual friction torque.