Control Valve Device for Electric Parking Brake

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current electric parking brake systems for commercial vehicles have complex and expensive control valve devices due to the need for multiple seals and complex geometries, particularly in 3/2-way valve configurations, which complicate the connection and separation of working connections, leading to reliability and cost issues.

Innovation Solution

A control valve device with a two-part pressure chamber and a simplified bistable valve structure, allowing all three working connections to be connected in one state and separated in another, reducing complexity and cost by using a design comparable to a 2/2-way valve with a spring-loaded switching piston and radial seals, enabling fluid-tight separation and connection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a 3/2-way valve configuration is used with multiple seals and complex geometry, then the valve can control multiple connections, but the device complexity and manufacturing cost increase significantly

Engineering Contradiction:
Improveconnection control capabilityVSAvoidvalve structure complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The pressure chamber is divided into two separate parts (first pressure chamber part and second pressure chamber part), each connected to different working ports. This segmentation allows independent pressure control while simplifying the overall valve structure and reducing seal requirements compared to a traditional 3/2-way valve configuration.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The control valve device provides universal functionality by enabling all three working ports to be interconnected through the two-part pressure chamber system. The valve can connect or disconnect any combination of ports (first, second, and third working ports) while maintaining a simpler structure than conventional 3/2-way valves, achieving multi-functionality without proportional complexity increase.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Reliability

If multiple axially vulcanized seals are used on the piston, then fluid-tight separation is achieved, but the manufacturing cost increases

Engineering Contradiction:
Improvefluid-tight separationVSAvoidmanufacturing cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The pressure chamber is segmented into two separate parts that can be independently pressurized. This segmentation reduces the sealing requirements compared to a single complex chamber, potentially reducing the number of expensive axially vulcanized seals needed while maintaining fluid-tight separation where required.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The control valve device uses a simplified piston design that copies the essential function of complex bistable valve pistons without replicating their complexity. By using a simpler piston structure with reduced seal requirements, the design achieves comparable reliability at lower manufacturing cost.

Inventive Principle:
Principle #26Copying

3Ease of operation

If air is guided through the valve piston, then the piston can be actuated, but two axially vulcanized seals are required increasing cost

Engineering Contradiction:
Improvepiston actuationVSAvoidseal requirement
Core Design Contradiction:
Ease of operationVSEase of manufacture

Solution Approach 1:

The pressure control is segmented into two independent parts, allowing the piston to be actuated by pressure differential across the two pressure chamber parts rather than requiring air to pass through the piston. This reduces the sealing requirements while maintaining actuation functionality.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The device uses pneumatic pressure applied to the two-part pressure chamber system to actuate the piston, replacing the need for air to pass through the piston itself. This approach maintains ease of operation through pneumatic actuation while reducing the number of seals required.

Inventive Principle:
Principle #29Pneumatics and hydraulics

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution simplifies the structure and operation of the control valve device, enhancing reliability and reducing production costs by allowing for a mechanically simpler and safer electric parking brake system with two distinct switching states, ensuring efficient pressure equalization and fluid exchange.

Implementation Method 1

a spring (9) by means of which the switching piston (8) is spring-loaded

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

The control valve assembly has at least two pressurized inlets to move the simplified piston into the open position

Methodology Applied
Scientific EffectPressure differential: Pressure Gradient

Data Source

PatentEP3402705B1Control valve device for an electric parking brake device, and electric parking brake device
Publication Date: 2020.03.25 KNORR BREMSE SYSTEME FUER NUTZFAHIZEUGE GMBH
  • EP3402705B1 patent drawingFigure 1
  • EP3402705B1 patent drawingFigure 2
  • EP3402705B1 patent drawingFigure 3

AI summary

The present invention relates to a control valve device (1) for an electric parking brake device (20) of a vehicle, in particular of a commercial vehicle, wherein the control valve device (1) comprises a first working connector (2), a second working connector (3), a third working connector (4), a housing (5), a housing chamber (6), a cylinder chamber (7), a switching piston (8) which is guided in the cylinder chamber of the housing, and a spring (9), by means of which the switching piston (8) is spring-loaded, wherein the housing chamber (6) is connected to the third working connector (4), wherein, furthermore, the control valve device (1) has a pressure chamber (10) which is split in two and to the first part region (10A) of which the first working connector (2) is connected and to the second part region (10B) of which the second working connector (3) is connected, wherein, in a first switching state of the control valve device (1), the first part region (10A) of the pressure chamber (10) which is split in two is separated from the second part region (10B) and from the housing chamber (6), in particular in a fluid-tight manner, and wherein, in a second switching state, the first part region (10A) of the pressure chamber (10) which is split in two is connected to the second part region (10B) and the housing chamber (6). Furthermore, the present invention relates to an electric parking brake device (20) for a pneumatic brake system of a vehicle, in particular a commercial vehicle, having a control valve device (1).