Pneumatic Brake Control Valve with Electronic-Pneumatic Redundancy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electronically controlled pneumatic brake systems in commercial vehicles lack a reliable fallback mechanism for safe and reliable braking, especially in automated driving scenarios where electronic control failures occur without driver intervention.
Innovation Solution
An electronically controllable brake system with a second control unit that enables electro-pneumatic redundancy by bypassing electrical control failures, allowing for automatic activation of the parking brake valve and bypass valve to ensure braking functionality, even without driver input.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Extent of automation
If electronic control valves are actuated by a control unit to control brake pressures in an automatically controlled vehicle, then automated braking functionality is improved, but reliability deteriorates because there is no electronically controllable fallback level if the electronic control fails
Solution Approach 1:
The system changes the control parameter from purely electronic to a dual-mode system that can switch between electronic control (normal operation) and pneumatic control (failure mode). The control valves are designed to accept both electronic control signals and pneumatic control pressures, allowing parameter change based on system state.
Solution Approach 2:
The system prepares a pneumatic fallback mechanism in advance that can be activated if electronic control fails. The control valves are pre-configured with pneumatic control inputs and are connected to the pneumatic brake system, so that upon electronic control failure, the pneumatic system can immediately take over without requiring additional components or complex activation sequences.
2Device complexity
If the pneumatic fallback level is designed to work only when the driver presses the brake pedal, then device complexity is reduced, but adaptability deteriorates because the fallback cannot activate automatically when no driver intervention is present
Solution Approach 1:
The control valves are designed with multi-functionality to serve both electronic control mode (for normal automated braking) and pneumatic control mode (for fallback operation). This universal design allows the same hardware to adapt to different operational modes without requiring separate dedicated components for each mode.
Solution Approach 2:
The system incorporates automatic failure detection and self-activation capability. When electronic control failure is detected, the system automatically switches to pneumatic control mode without requiring driver intervention or manual activation, enabling the fallback system to serve itself by detecting its own need for activation.
3Reliability
If a second control unit with parking brake valve and bypass valve is added for electronic-pneumatic redundancy, then reliability is improved, but device complexity increases
Solution Approach 1:
The system merges the fallback control functionality into the existing control valve structure by adding pneumatic control capabilities to the same valves used for electronic control. The bypass valve is integrated into the existing pneumatic line architecture, combining multiple functions (electronic control, pneumatic control, and bypass) into a unified system rather than adding completely separate redundant systems.
Solution Approach 2:
The control valves are designed to perform multiple functions: electronic control in normal operation, pneumatic control in failure mode, and bypass functionality for pressure equalization. This multi-functionality reduces the need for separate dedicated components for each control mode, thereby limiting the increase in device complexity while achieving electronic-pneumatic redundancy.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to an electronically controllable pneumatic brake system (100), comprising: at least two brake circuits (A, B, C), wherein at least one of the at least two brake circuits (A, B, C) is assigned an electrically and pneumatically controllable control valve (11, 13) for specifying brake pressures (p1, p2, p3, p4, pPB) for controlling wheel brakes (1, 2, 3, 4) of the associated brake circuit (A, B, C); and a first control unit (110), which is designed to electrically control the control valve (11, 13) in question in accordance with a vehicle target deceleration (zSoll) requested in an automated manner or in accordance with an actuation (ds) specified by the driver by means of an actuation device (24a). According to the invention, at least one bypass valve (21) associated with a control valve (11, 13) is also provided, which bypass valve is designed to pneumatically (pA, pB) control the associated control valve (11, 13), wherein the pneumatic control (pA, pB) is performed in accordance with the vehicle target deceleration (zSoll) requested in an automated manner or in accordance with the actuation (ds) specified by the driver.