Trailer Maneuvering Drive Release Cable PWM Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing maneuvering drives for trailers lack operational reliability, particularly in ensuring safe activation and deactivation of drive units and swivel motors to prevent unintended movement or braking during tractor coupling and uncoupling.
Innovation Solution
A pulse-width-modulated enable signal is transmitted via an enable line between the central unit and each drive unit, using specific modulation degrees to differentiate between blocking, partial, and full enable states, with 0% and 100% modulation interpreted as blocking signals, and 25% and 80% modulation enabling drive motors and swivel motors respectively, while preventing unintentional swivel motor activation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a simple activation signal is used to control drive units and swivel motors, then the control system is simple, but operational reliability deteriorates due to risk of unintended activation
Solution Approach 1:
The patent applies parameter changes by using pulse-width modulation (PWM) with specific duty cycle ranges to encode different activation states. The control signal varies the duty cycle parameter within defined ranges: 0-20% for blocked state, 21-80% for drive motor enabled, and 81-100% for swivel motor enabled. This parameter-based encoding ensures reliable differentiation between states without requiring complex signal protocols or additional hardware.
2Adaptability or versatility
If the swivel motor can be freely activated to engage pressure rollers with wheels, then maneuvering flexibility is improved, but safety deteriorates due to risk of unintended braking or movement
Solution Approach 1:
The patent implements preliminary action by requiring a specific two-stage activation sequence. The drive motor must be enabled first (duty cycle 21-80%) to prepare the drive roller for operation. Only after the drive motor is active can the swivel motor be enabled (duty cycle 81-100%) to engage the pressure roller with the wheel. This preliminary preparation ensures that the wheel is ready to be driven before the pressure roller engages, preventing unintended braking or movement while maintaining maneuvering flexibility.
Data Source
Figure 1
Figure 2
AI summary
The drive has two drive units (24) attached to wheels (16) of a trailer (10), and a release cable provided between a central unit and the drive units. A pulse width-modulated release signal is transmitted via the release cable. A modulation factor is interpreted by the drive units as an activation condition and set between 0-100 percent. A drive motor (26) and an engine brake of the drive units are released in the activation condition. A pivoting motor of the drive units is released in another activation condition. The release signal is modulated with a frequency of 2 kilo Hertz.