Fifth Wheel Safety Arrangement with Position Sensor

Solution Overview

Problem

Drivers often disregard safety requirements when adjusting fifth wheels on towing vehicles, leading to risks during cable disconnection or reconnection, particularly when the trailer is not properly locked, which can result in accidents, especially on slopes.

Innovation Solution

A safety arrangement that includes a sensor detecting the fifth wheel's position and connecting to the vehicle's electrical management system to restrict engine speed when the fifth wheel is in its rear position, preventing unsafe movement by limiting vehicle speed to 10mph, thus ensuring the driver is aware of the critical position and discouraging risky behavior.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the fifth wheel is positioned at the rearmost position to allow driver access for cable connection, then the driver can safely connect/disconnect cables, but the overall vehicle length exceeds legal limits and the risk of accidental movement increases

Engineering Contradiction:

Improvedriver access for cable connectionVSAvoidrisk of accidental trailer movement

Core Design Contradiction:

Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The system applies preliminary anti-action by automatically engaging the trailer brakes and restricting vehicle speed before the driver can accidentally move the vehicle with the trailer disconnected. The sensor detects the rear position and preemptively activates safety measures including brake engagement and speed limitation, preventing the harmful effect of accidental movement before it can occur.

Inventive Principle:

Principle #9Preliminary anti-action

Solution Approach 2:

The system implements feedback by using a sensor to detect the fifth wheel position and automatically responding with brake engagement and speed restriction when the rear position is detected. This closed-loop feedback mechanism ensures that the safety measures are activated only when needed, maintaining normal operation during safe conditions while preventing accidents when the trailer is vulnerable.

Inventive Principle:

Principle #23Feedback

2Ease of operation

If the fifth wheel is positioned at the rearmost position, then the gap between trailer and cab is sufficient for cable operations, but the combination exceeds legal length limits for highway travel

Engineering Contradiction:

Improvegap size for cable operationsVSAvoidoverall vehicle length

Core Design Contradiction:

Ease of operationVSLength of moving object

Solution Approach 1:

The system applies dynamics by making the fifth wheel position adjustable rather than fixed. The slider carriage mechanism allows the fifth wheel to be dynamically repositioned between front and rear positions, enabling the driver to optimize the gap size for cable operations when needed while retracting to standard positions for highway travel to comply with length limits.

Inventive Principle:

Principle #15Dynamics

3Productivity

If the vehicle speed is unrestricted when the fifth wheel is in the rear position, then the driver can maneuver the vehicle efficiently, but the trailer may move unexpectedly causing accidents

Engineering Contradiction:

Improvevehicle maneuvering efficiencyVSAvoidtrailer connection stability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The system applies preliminary anti-action by automatically engaging the trailer brakes and restricting vehicle speed before the driver can accidentally move the vehicle with the trailer disconnected. The sensor detects the rear position and preemptively activates safety measures including brake engagement and speed limitation, preventing the harmful effect of accidental movement before it can occur.

Inventive Principle:

Principle #9Preliminary anti-action

Solution Approach 2:

The system implements feedback by using a sensor to detect the fifth wheel position and automatically responding with brake engagement and speed restriction when the rear position is detected. This closed-loop feedback mechanism ensures that the safety measures are activated only when needed, maintaining normal operation during safe conditions while preventing accidents when the trailer is vulnerable.

Inventive Principle:

Principle #23Feedback

Data Source

PatentEP1717134B1Fifth wheel safety arrangement

Publication Date: 2009.05.06 FONTAINE INT EURO

Figure 1
Figure 2
Figure 3~4

AI summary

At the rear of a towing vehicle for attachment of a trailer, a fifth wheel (10) is mounted upon a slider carriage (12) which is slidably displaceable upon a slider frame (14) between predetermined front and rear positions, for example as defined by notches (17, 27), relative to intended direction of vehicle travel. A sensor (26) detects when the fifth wheel (10) is in its rear position and the sensor (26) is connected to the electrical management system of the towing vehicle so as to limit the operation or speed of the vehicle whenever the fifth wheel is in its rear position.