IPGATE AG – Patent Family E150 · System-Wide Multimodal Self-Diagnosis (SMSD)

E150 – System-Wide Multimodal
Self-Diagnosis (SMSD)

On-board diagnostic method for electrohydraulic brake systems — detecting seal and valve integrity using the pressure supply unit's own sensors (piston position, pressure, motor current) without external testing equipment, operable during or after driving. 1 invention concept · 3 granted rights · DE · US · CN · JP

E150 – Brake system with pressure supply unit (DV), piston-cylinder unit (18, D), sensors (8a, 15), isolation valves (TV1/TV2), switching valve (SV), wheel brakes and pressure sensor
Figure 1 – Brake System with Pressure Supply Unit (DV), Piston-Cylinder Unit (18, D), Sensors (8a, 15), Isolation Valves (TV1/TV2), Switching Valve (SV), Wheel Brakes (B, HLa, HLb) and Pressure Sensor (P/U)
Applicant IPGATE AG, Churerstrasse 160a, 8808 Pfäffikon (CH)
Inventors Heinz Leiber, Dr. Thomas Leiber, Dr. Anton van Zanten
Priority / Filing Date July 14, 2016 (DE 10 2016 112 971.2) · PCT: July 4, 2017
PCT Application PCT/EP2017/066653 (WO 2018/011021 A1)
Technology Sensor-based self-diagnosis using the existing piston-cylinder pressure supply unit — three alternative diagnostic modes evaluating piston movement, generated pressure, and/or motor current to assess tightness and functionality of seals, valves, and hydraulic lines
Innovations 1 independent invention concept (method) · 4 family members across 4 jurisdictions
3
Granted Rights
4
Jurisdictions
3
Diagnostic Modes
2016
First Priority
SMSD
Self-Diagnosis

On-Board Self-Diagnosis
Without External Equipment

Patent family E150 describes a diagnostic method for hydraulic vehicle components — specifically for determining the tightness of seals and valves in electrohydraulic brake systems — using the sensor technology already present in the electrically driven pressure supply unit, with no need for external testing devices.

The core idea is that the piston-cylinder pressure supply unit (PSU) itself acts as a diagnostic instrument. By evaluating piston position and movement, the pressure generated, and/or the drive motor current under defined operating conditions, the system can assess the integrity of seals, valves, and hydraulic lines across the entire brake circuit — a system-wide, multimodal approach.

The diagnosis can be performed during normal driving operation or after a braking event, without interrupting vehicle function and without external workshop equipment. All four family members (DE, US, CN, JP) claim the same fundamental diagnostic method; differences between jurisdictions relate to scope of protection and specification of diagnostic timing rather than to distinct inventions. The family's inventors include Dr. Anton van Zanten, internationally recognized as the co-inventor of ESP (Electronic Stability Program).

DE US CN

From Pressure Control to Self-Diagnostic Systems

The predecessor families E147–E149 addressed valve architecture, pressure supply, and physical integration of brake-by-wire components. E150 takes a fundamentally different step: rather than optimizing how pressure is generated or distributed, it introduces on-board intelligence for assessing the health of the hydraulic system itself.

Prior Art Limitation: Traditional diagnosis of hydraulic brake components — detecting seal leaks, valve malfunctions, or line restrictions — typically requires specialized workshop equipment, dedicated test cycles, or physical disassembly. In-vehicle OBD systems for hydraulic brakes have historically been limited to binary fault detection (e.g., pressure threshold violations) rather than continuous, quantitative condition monitoring.

As brake-by-wire systems become more prevalent — particularly in electrified and autonomous vehicles — the demand for predictive, hardware-free self-diagnosis increases sharply. Safety regulations for automated driving require continuous monitoring of brake system integrity. Electrohydraulic pressure supply units, by virtue of their motorized piston-cylinder architecture, already contain all necessary sensors: position sensors, pressure sensors, and motor current measurement.

E150 Advance: The SMSD method repurposes the PSU's own actuator and sensors as a diagnostic instrument. By comparing measured piston movement, pressure response, and motor current against expected values from known-good characteristics, the system detects deviations indicative of seal leaks, valve blockages, or line restrictions — continuously, during operation, without additional hardware. This represents a decisive step toward self-diagnosing, predictively maintainable brake-by-wire systems.

The three diagnostic modes are designed to complement each other: Mode A detects bulk leakage via piston drift under constant force; Mode B detects flow resistance and pressure generation capacity via stroke-referenced measurement; Mode C detects slow leaks via pressure decay monitoring with the piston stationary. Together they provide comprehensive, fault-discriminating coverage of the hydraulic circuit.

Three Alternative Diagnostic Modes

The single SMSD invention encompasses three alternative diagnostic modes that can be applied individually or in combination during or after driving, using the PSU's existing sensors. All modes assess seal, valve, and line integrity without external equipment.

Mode A · Piston Movement
Constant-Force Drift Detection
DE · US · CN · JP
Measurement of piston position or movement under a constant or approximately constant drive force applied to the piston-cylinder unit. Leaks in seals or valves manifest as unexpected piston displacement — volume flowing out of the circuit causes the piston to drift. Sensitive to bulk leakage across any component downstream of the PSU.
Mode B · Pressure & Current
Stroke-Referenced Pressure/Current Measurement
DE · US · CN · JP
Measurement of the generated pressure and/or motor current at a predetermined piston stroke position. Deviations from expected pressure-volume or current-force characteristics indicate valve blockages, partial occlusions, or abnormal flow resistance in the hydraulic circuit. Enables quantitative condition assessment of individual valve states and line condition.
Mode C · Pressure Decay
Static Pressure Change (dp/dt) Monitoring
DE · US · CN · JP
Measurement of the pressure change over time (dp/dt) with the piston held stationary. Slow pressure decay in a nominally sealed system indicates micro-leaks in seals or valve seats that would not be detectable by the piston drift method. Provides continuous background monitoring during periods when the PSU is not actively supplying pressure.
Section 1 · Invention Overview

Invention Description & Keywords

One independent invention concept (method), claimed across 4 jurisdictions. Scope differences between jurisdictions relate to claim breadth and diagnostic timing specification, not to distinct inventions.

Ref. · Jurisdictions Cat. Description Keyword
E150 A1
DE · US 11,279,337 B2 · CN 109476300 B · JP 7003106 B2		 Method Diagnostic procedure for vehicle hydraulic components using an electrically driven piston-cylinder unit as pressure supply. Three alternative diagnostic modes: (a) measurement of piston movement at constant/approximately constant drive force; (b) measurement of pressure and/or motor current at a predetermined piston stroke; (c) measurement of pressure change dp/dt over time with the piston stationary. Enables assessment of tightness, flow resistance, and functionality of seals, valves, and lines — operable during or after driving without external testing devices. SMSD · Piston drift · Pressure/current · dp/dt · No external equipment
Section 2a · Family Overview

Jurisdictions & Status

All members of the E150 patent family as of February 2026. 3 granted rights; DE application pending.

File No. Country Status Type Registration No. Filed Grant No. Granted
E150DE DE Pending Patent 102016112971.2 Jul. 14, 2016 — —
E150WOUS US Granted Patent 16/316,425 Jul. 4, 2017 US 11,279,337 B2 Mar. 22, 2022
E150WOCN CN Granted Patent 201780043741.X Jul. 4, 2017 CN 109476300 B Nov. 5, 2021
E150WOJP Granted Patent 2019-501669 Jul. 4, 2017 JP 7003106 B2 Jan. 5, 2022