Hydraulic Steering Arrangement with Parallel Amplification Flow Paths
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hydraulic steering arrangements face challenges in adapting steering behavior to different operating conditions, such as on-road and off-road use, as existing systems lack flexibility in controlling fluid flow to accommodate varying steering demands.
Innovation Solution
The introduction of a third amplification flow path in parallel to the second flow path, equipped with a valve that allows for multiple control options, including on/off or pulse width modulation, enabling adjustable fluid supply to the working port arrangement, and allowing for different amplification characteristics and progressive steering responses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a single amplification flow path is used, then the steering arrangement has a fixed steering behavior, but it cannot adapt to different operating conditions such as on-road and off-road use
Solution Approach 1:
The single amplification flow path is segmented into multiple parallel flow paths (second and third flow paths), each with independent valve control. This allows the system to selectively activate different flow paths based on operating conditions, enabling adaptation of steering behavior without requiring a complete system redesign.
Solution Approach 2:
The system transitions from a static single flow path configuration to a dynamic multi-path configuration where valves can selectively open or close flow paths based on real-time operating conditions. This dynamic reconfiguration enables the steering arrangement to adapt its characteristics according to whether the vehicle is operating on-road or off-road.
2Adaptability or versatility
If multiple amplification flow paths are added to enable flow adjustment, then steering behavior flexibility is improved, but the device complexity increases
Solution Approach 1:
The multiple amplification flow paths are designed with different amplification characteristics (e.g., 100%, 150%, 200% amplification), allowing a single hydraulic steering arrangement to serve multiple functions: normal steering, enhanced steering for off-road conditions, and variable steering ratios. This multi-functionality reduces the need for separate steering systems for different operating conditions.
Solution Approach 2:
The system changes the flow parameters by selectively activating different amplification flow paths with distinct amplification characteristics. By varying which flow paths are active and their degree of opening, the system can continuously adjust the steering ratio and response characteristics to match different operating conditions without physical modification.
3Ease of operation
If on/off valves are used for simple control, then the control system is easy to operate, but the flow control precision is limited
Solution Approach 1:
The system employs pulse width modulated (PWM) valves that operate by periodically opening and closing the flow paths with varying duty cycles. This periodic action allows precise control of the average flow rate through the amplification flow paths while maintaining the simplicity of binary valve actuation. The duty cycle percentage directly controls the effective flow, providing both ease of operation and precise flow control.
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
This configuration allows for flexible steering behavior adjustments by enabling maximum, throttled, or exclusive flow paths, accommodating various steering conditions and vehicle parameters, enhancing operational versatility and driver convenience.
Implementation Method 1
Hydraulic fluid is supplied to the working port arrangement via the first flow path and via the second flow path
Implementation Method 2
a second amplification flow path in form of a third flow path bridging the steering unit and having a second amplification orifice which is controlled as a function of the steering unit
Data Source
AI summary
A hydraulic steering arrangement 1 is described comprising a supply port arrangement having a pressure port (4) and a tank port (5), a working port arrangement having two working ports (6, 7), a steering unit (2) arranged in a flow path (9) between the supply port arrangement (4, 5) and the working port arrangement (6, 7), and a second flow path (13) in form of an amplification flow path bridging the steering unit (2) and having an amplification orifice (AU1) which is controlled as function of the steering unit (2). Such a steering arrangement should have a possibility to change the steering behaviour. To this end at least a third flow path (14) in form of an amplification flow path is arranged in parallel to the second flow path (13), wherein the second/or the third flow path (13, 14) comprise an valve (15).