Three-Pivot Drawbar Layout for Heavy Trailer Steerability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Towing vehicles with rigid chassis experience difficulty in maneuverability and steerability when towing heavy trailers due to the large turning radius and lever arm effect, which can cause the front wheels to lift off the ground, especially when hauling heavy loads uphill, necessitating additional weights that increase the overall mass and fuel consumption.

Innovation Solution

A towing arrangement with a drawbar system that includes three separate pivots - a transverse, vertical, and longitudinal pivot - to distribute the towing force more effectively, keeping the front wheels grounded and improving steerability by locating the pivot point below the chassis, allowing the trailer to tilt and conform to ground form.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a conventional rigid tow bar is used, then structural strength is maintained, but flexibility and comfort are reduced due to road imperfections being transmitted directly to the towing vehicle

Engineering Contradiction:
Improvestructural strengthVSAvoidvibrations and shocks from road imperfections
Core Design Contradiction:
StrengthVSObject-affected harmful factors

Solution Approach 1:

The patent applies flexible elements including rubber buffers and spring mechanisms within the tow bar assembly. These flexible components absorb vibrations and shocks from road imperfections while maintaining the structural integrity of the rigid tow bar, thus resolving the contradiction between strength and comfort.

Inventive Principle:
Principle #30Flexible shells and thin films

Solution Approach 2:

The patent incorporates buffers and shock-absorbing elements in advance within the tow bar structure. These elements are pre-positioned to cushion impacts and vibrations before they reach the towing vehicle, preventing harmful transmissions while maintaining structural strength.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

2Ease of manufacture

If a fixed, non-adjustable tow bar is used, then manufacturing simplicity is maintained, but adaptability to different trailers and towing scenarios is reduced

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoidadaptability to different trailers
Core Design Contradiction:
Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The patent implements adjustable length mechanisms and configurable connection points on the tow bar. These dynamic features allow the tow bar to be adjusted for different trailer sizes and towing scenarios while maintaining a relatively simple overall structure, balancing manufacturing ease with adaptability.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The tow bar is divided into modular sections with standardized connection interfaces. This segmentation allows for easy adjustment of length and configuration while maintaining manufacturing simplicity through standardized components, enabling adaptability to different trailers.

Inventive Principle:
Principle #1Segmentation

3Strength

If heavy-duty materials are used throughout the entire tow bar, then strength and durability are improved, but weight increases which affects fuel efficiency

Engineering Contradiction:
Improvestrength and durabilityVSAvoidweight of tow bar
Core Design Contradiction:
StrengthVSWeight of moving object

Solution Approach 1:

The patent applies heavy-duty materials and reinforced structures only at critical load-bearing points and high-stress areas of the tow bar. Other sections use lighter materials, optimizing the balance between strength/durability and weight to improve fuel efficiency while maintaining necessary strength.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP4217214B1Towing arrangement for a towing vehicle, system, trailer, and method
Publication Date: 2026.05.06 SLEIPNER GROUP OY
  • EP4217214B1 patent drawingFigure 1
  • EP4217214B1 patent drawingFigure 2
  • EP4217214B1 patent drawingFigure 3a

AI summary

The invention relates to a towing arrangement (10) for a towing earth-moving vehicle (12), the towing earth-moving vehicle (12) comprising a towing point (24) fitted under its chassis (14), which towing arrangement (10) includes a drawbar (26) arranged to be pivoted to the towing vehicle's (12) towing point (24) and a second end (29) comprising the drawbar's (26) towing point (30) for the device (100) to be towed, a first pivot (32) for pivoting the drawbar (26) under the rear axle (20) to the towing vehicle's (12) towing point (24) formed under the towing vehicle's (12) chassis (14), which first pivot (32) is in the transverse direction of the chassis (14), a second pivot (34) fitted to the drawbar's (26) second end (29), which second pivot (34) is vertical and arranged to transmit the load of the trailer (56) being towed rigidly to the first pivot (32), and a third pivot (44), located at one end (28, 29) of the drawbar (26), equipped with a shaft in the towing vehicle's (12) longitudinal direction, thus permitting the device (100) to tilt in the towing vehicle's (12) transverse direction, in which the towing arm (64) is rigidly attached to the drawbar's (26) rearmost pivot (34, 44). The invention also relates to a system, a trailer, and a method.