Speed-Adaptive Hydraulic Axle Control for Working Machines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing working machines experience instability due to abrupt switching between axle pivoting modes when encountering ground irregularities, which can be disconcerting for operators and affect machine stability, especially when handling loads at height or on uneven surfaces.
Innovation Solution
A hydraulic system that controls axle movement based on machine speed by varying fluid flow restriction through an electrically operated control valve, allowing continuous adjustment between locked and free pivoting modes, and includes auxiliary inputs for stabilizer and sway actuators to maintain stability during operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If automatic switching between axle pivoting modes is implemented, then machine stability is improved, but operator comfort deteriorates due to disconcerting mode changes
Solution Approach 1:
The patent implements dynamic control of the hydraulic system by continuously adjusting the flow restriction based on machine speed rather than switching between discrete modes. The control system varies the restriction to fluid flow proportionally with speed changes, creating a smooth, continuous transition that adapts to operating conditions without abrupt mode changes, thereby maintaining stability while improving operator comfort.
2Stability of the object's composition
If axle pivoting is restricted when stationary, then machine stability is improved, but ability to handle uneven ground deteriorates
Solution Approach 1:
The patent changes the parameter of fluid flow restriction dynamically based on machine speed. When stationary or at low speeds, the system provides greater flow restriction to maintain stability during load handling. As speed increases, the restriction is reduced proportionally, allowing the axle to pivot freely to accommodate uneven ground. This continuous parameter adjustment resolves the contradiction between stability and adaptability.
3Adaptability or versatility
If free axle pivoting is permitted, then ability to handle ground irregularities is improved, but machine stability deteriorates during load handling
Solution Approach 1:
The control system uses feedback from machine speed sensing to continuously adjust the hydraulic flow restriction. Speed sensor input provides real-time information about machine operation state, and the controller modulates the control valve accordingly - restricting flow at low speeds for stability during load handling, and permitting free flow at higher speeds to accommodate ground irregularities. This feedback-based continuous adjustment eliminates the need for abrupt mode switching.
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 system provides continuous and smooth transition between axle movement modes, enhancing stability and preventing axle movement when stationary, while allowing free movement at higher speeds, ensuring maximum stability during load handling and operation on uneven surfaces.
Implementation Method 1
the controller responds by varying the restriction to fluid flow between the control actuators occurring as a result of the control actuators extending or retracting
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A working machine (10) which includes a body (12) and an axle (18) which is mounted so as to be moveable relative to the body (12), the axle (18) carrying at or towards each end, a ground engaging wheel (20) by means of which the machine (10) is moveable on the ground, the machine (10) including a speed sensor (39) sensitive to the machine ground speed, and there being a hydraulic control system (42) including at least one control actuator (55, 56) connected between the body (12) and the axle (18) for controlling movement of the axle (18) relative to the body (12), and the hydraulic system (42) further including at least one control valve (58, 59) which is operable to restrict fluid flow occurring as a result of the control actuator (55, 56) extending or retracting in response to axle (18) movements relative to the body (12), by an amount depending upon a machine speed signals provided by the speed sensor (39) wherein the control valve (58, 59) is an electrically operated control valve, operated proportionally by a valve controller (40) which responds to changes in machine speed, by adjusting the restriction to fluid flow so as to permit more fluid flow as the machine speed increases.