Pressure-Controlled Switching Device for Axle Torque Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing drive-train systems for motor vehicles, particularly agricultural and municipal vehicles, face challenges in managing torque transmission during braking, where prolonged high torque can lead to axle overload, conflicting with the need for maximum braking power, especially when towing unbraked trailers, resulting in braking force loss due to dynamic axle load distribution.
Innovation Solution
A method that automatically connects a further axle to the drive axle via a pressure-controlled switching device when the service brake is actuated, using different control pressures to transmit varying torque levels based on braking modes, allowing for prolonged all-wheel operation without damage in regular braking and maximum deceleration in emergency braking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If the full braking power is transmitted to the connected axle to achieve maximum deceleration, then the braking performance is improved, but the axle transmission is overloaded and damaged
Solution Approach 1:
The switching device transitions from a static on/off state to a dynamic, continuously controllable state. By applying different control pressures, the device can modulate torque transmission in real-time, allowing the system to adapt braking force distribution dynamically between the drive axle and connected axle based on operational conditions, thus preventing overload while maintaining braking effectiveness
Solution Approach 2:
The invention changes the control parameter of the switching device from binary (connected/disconnected) to continuous control pressure levels. By varying the control pressure applied to the switching device, the system can precisely regulate the torque transmission characteristic, enabling smooth transition between different braking modes and protecting the axle transmission from excessive torque while maintaining full braking capability when needed
2Reliability
If the switching device interrupts the driving connection to protect the axle transmission, then the axle is protected from overload, but the braking force is reduced
Solution Approach 1:
The switching device serves as an intermediary element between the drive axle and the connected axle. Rather than completely disconnecting the axle transmission during braking, the device acts as a torque regulator, mediating the force transmission by allowing controlled torque passage through the switching device while preventing excessive torque that would damage the axle transmission
Solution Approach 2:
The system dynamically adjusts the engagement state of the switching device during braking operations. Instead of a fixed disconnected state, the switching device maintains a controlled engagement that allows sufficient torque transmission for braking while limiting maximum torque to protect the axle transmission, achieving both protection and braking force simultaneously
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
Ensures controlled torque transmission to prevent axle overload while maintaining all-wheel operation and ensuring maximum braking power is available when needed, thereby enhancing the safety and efficiency of the drive-train system.
Implementation Method 1
a pressure-controlled switching device (5), wherein the automatic connection of the further axle (9) takes place by actuation of the switching device (5) when a service brake system (4) of the motor vehicle is actuated
Data Source
AI summary
A method of operating a drive-train of a vehicle having a drive engine, at least one drive axle and at least one further axle which can be drivingly connected by a pressure-controlled switching device. The switching device is acted upon by an opening pressure to disconnect the axle. When a service brake system of the vehicle is actuated, the axle is automatically connected by actuating the switching device, which is actuated as a function of a braking mode determined during actuation of the brake system, in such manner that when the brake system is actuated in a first braking mode, the switching device is actuated by a first control pressure to transmit a first torque, and if at least one parameter that characterizes the occurrence of a second braking mode is exceeded, the switching device is actuated by a second control pressure to transmit a second, higher torque.