IPGATE AG – Patent Family E145 · Floating Piston Brake System with HDS 2 & THZ Diagnosis
5
Granted Rights
4
Jurisdictions
7
Independent Inventions
2015
First Priority
HDC 2.0
Control Technology

Floating Piston Brake System
with HDS 2 & THZ Diagnosis

Patent family E145 claims a complete brake system integrating the second-generation HDS (MUX 2.0) pressure control into a floating piston master cylinder architecture — extending the scope beyond pure control methods to cover the combined brake system and self-diagnosis.

The E145 builds on two predecessor patent families: E102 defines the basic principle of highly dynamic pressure control (HDS generation 1) — volume control with a plunger as a bidirectional control element and PWM valve modulation for wheel-selective pressure regulation. E141 (used as priority for E145) expands the control system in multiple dimensions: pressure reduction via outlet valves as an additional degree of freedom, three pump types, and a solution to the volume problem with single-stroke pistons.

While E141 protects the control method (HDS 2) in isolation, E145 goes a decisive step further: it claims a complete brake system with a floating piston master cylinder unit in which HDS 2 (referred to as MUX 2.0) is systemically integrated. The scope of protection is therefore broader — encompassing the combination of brake system architecture and control strategy. E145 further introduces two novel THZ diagnostic methods that, for the first time, functionally monitor the mechanical return element (floating piston) during both driving and parking modes.

EP · DE US CN DE (Utility Model)

HDS Generations & Nomenclature

The Highly Dynamic pressure control System (HDS) is a proprietary IPGATE control strategy for electrohydraulic brake actuators. E145 implements HDS generation 2 in three pump-type variants, collectively referred to as MUX 2.0 in the context of this patent family.

Variant Pump Type Control Strategy
HDS 2.1 Plunger Volume control — pressure build-up/reduction + outlet valve(s)
HDS 2.2 Double-acting piston (DHP) Volume control — pressure build-up/reduction + outlet valve(s)
HDS 2.3 Rotary pump Volume control only — pressure build-up + outlet valve(s) for reduction
Prior Art Limitation (E102 / HDS 1): The first-generation HDS (E102) provided volume control with a plunger as a bidirectional control element but lacked integrated outlet valve modulation for simultaneous multi-wheel pressure reduction and did not incorporate floating piston master cylinder diagnosis.
E145 Advance: Simultaneous volume control of the pressure supply and pressure reduction via outlet valves in a floating piston brake system enables wheel-specific pressure build-up and reduction in highly dynamic braking situations (ABS/ESP) — with full THZ self-monitoring via radial channel and pressure profile analysis.

Three Core Innovation Areas

The seven independent inventions of E145 fall into three thematic groups, each addressing a distinct functional aspect of the integrated brake system.

Innovation 1
HPC 2 – Highly Dynamic Pressure Control
US C1 · CN C1 · EP C1 · EP1 C14
Floating piston brake system with simultaneous volume and valve control (MUX 2.0 / HDS 2) for wheel-specific pressure build-up and reduction in highly dynamic braking situations. Extends to vibration damping, cross-wheel pressure control, and full by-wire capability (EP partial application).
Innovation 2
THZ Diagnosis – Driving Mode
US C34 · CN C34
Method for testing the tightness and mobility of the floating piston during driving. A radial channel in the master brake cylinder enables a pressure difference that moves the floating piston; the measured test path profile is compared against a target value profile to detect leakage or mechanical failure.
Innovation 3
THZ Diagnosis – Parking Mode
US C39
Method for testing the floating piston at standstill: pressure is stored in the second brake circuit, reduced in the first circuit, and valves are opened so the floating piston moves under pressure difference until equalization — enabling functional verification without driving input.
High-Pressure Relief (CN only, C36): A dedicated procedure handles pressure relief at ≥100 bar: multi-stage release via pressure relief valve, forward and return strokes of the double-acting piston with pressure-volume control, and subsequent repositioning — ensuring safe operation under extreme braking loads.
Section 1 · Invention Overview

Independent Claims, Descriptions & Keywords

Each independent claim is listed separately. 5 granted property rights across US, EP, CN, and DE with overlapping claim scope covering device and method inventions.

File · Claim Cat. Description Keyword
E145WOUS C1
US10,688,979 B2
Device Floating piston brake system with HDS 2 – simultaneous volume control of the pressure supply and pressure reduction via outlet valves for wheel-specific pressure build-up/reduction in highly dynamic braking situations (ABS/ESP). HDS 2 · Volume control · Simultaneous
E145WOUS C34
US10,688,979 B2
Method Method for testing tightness and mobility of the floating piston during driving. Radial channel in the master brake cylinder, pressure difference moves the floating piston; test path profile compared with target value profile. THZ diagnosis · Channel · Test path profile
E145WOUS C39
US10,688,979 B2
Method Method for testing the floating piston in parking mode. Pressure stored in second brake circuit, reduced in first circuit, valves opened — floating piston moves due to pressure difference until pressure equalization is reached. THZ parking · Pressure storage · Equalization
E145WOCN C1
CN107428325B
Device CN equivalent of HDS 2 pressure control: brake device with floating piston master cylinder, combined volume and valve control for simultaneous highly dynamic pressure changes in the wheel brakes. HDS 2 · Volume control · Simultaneous
E145WOCN C34
CN107428325B
Method CN equivalent of THZ driving diagnosis: method for testing the mobility and tightness of the floating piston via radial channel, pressure-volume curve, and comparison with a theoretical curve. THZ diagnosis · Pressure-volume curve
E145WOCN C36
CN107428325B
Method High-pressure relief procedure at pressures ≥100 bar: multi-stage release via pressure relief valve, forward stroke and return stroke of the double-acting piston with pressure-volume control, followed by repositioning. Pressure relief · ≥100 bar · Multi-stage
E145WOEP C1
EP3271227B1
Device EP equivalent of HDS 2: floating piston brake system with simultaneous volume and valve control for highly dynamic pressure changes in ABS/ESP scenarios. Scope does not include THZ diagnosis claims. HDS 2 · Volume control · ABS/ESP
E145WOEP1 C14
EP21202586.0
Device EP partial application: HPC 2.1 extended pressure control with active volume control for vibration reduction and cross-wheel pressure control. Fully by-wire capable. Broadens scope of original EP claim. HPC 2.1 · Vibration damping · By-wire
Section 2a · Family Overview

Jurisdictions & Status

All members of the E145 patent family as of February 2026. All five rights are granted or registered.

File No. Country Status Type Registration No. Filed Grant No. Granted
E145WOUS US Granted Patent 15/558,376 Dec. 30, 2015 US 10,688,979 B2 Jun. 23, 2020
E145WOEP EP Granted Patent 15817422.7 Dec. 30, 2015 EP 3271227 B1 Oct. 20, 2021
E145WOEPDE DE Granted Patent (via EP) 15817422.7 Dec. 30, 2015 502015015331.8 Oct. 20, 2021
E145WOCN CN Granted Patent 201580077961.5 Dec. 30, 2015 CN 107428325 B May 14, 2021
E145GDE DE Registered Utility Model 202015008975.5 Dec. 30, 2015 DE 202015008975 Jul. 21, 2016
IPGATE AG · Patent Family E145 · As of February 2026 PCT/EP2015/081401 · Priority March 2015