Overview
ISO 6489-4:2004 is an international standard developed by the International Organization for Standardization (ISO) that specifies the dimensional requirements for piton-type coupling devices used on agricultural towing vehicles. This standard applies specifically to mechanical connections between towing tractors and towed non-balanced trailers or implements equipped with coupling rings as defined by ISO 5692-1. The primary goal of ISO 6489-4:2004 is to ensure interchangeability and compatibility of piton-type couplings for agricultural vehicles under conditions where the vertical static load does not exceed 30 kN.
By standardizing these dimensions and design requirements, ISO 6489-4:2004 promotes safety, reliability, and operational efficiency in agricultural vehicle coupling systems.
Key Topics
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Scope and Application:
Defines the size and placement dimensions for piton-type coupling devices on agricultural towing vehicles with non-balanced trailers and semi-mounted implements, where the vertical static load ≤ 30 kN.
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Coupling Components:
Includes detailed descriptions of:
- Piton coupling pin
- Mounting plate
- Locking (closure) plate to prevent accidental decoupling.
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Dimensional Requirements:
Specifies precise measurements for the piton coupling components to fit with coupling rings standardized in ISO 5692-1. Critical dimensions include:
- Locking plate envelope and maximum clearance to avoid unintentional disengagement (≤ 10 mm gap).
- Pin geometry and plate positions to ensure secure attachment within specified tolerance zones.
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Mounting Position:
Establishes the location of the piton-type coupling relative to the tractor’s longitudinal axis and power take-off (PTO) shaft, preventing interference with tractor operation and ensuring sufficient articulation angles.
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Articulation Angle:
Requires a yaw angle of 60° for the coupling, accommodating tractor and implement movement. It acknowledges that tire width and adjustment settings may affect this angle and requires appropriate operator information labeling.
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Interoperability:
Details recommended combinations of mechanical linkages between towing and towed vehicles, ensuring compatibility across different coupling types and trailer ring standards.
Applications
ISO 6489-4:2004 is essential for manufacturers, designers, and users of agricultural machinery involved in coupling tractors with trailers and implements. Its practical uses include:
Open preview (PDF)Agricultural vehicles — Mechanical connections between towed and towing vehicles — Part 4: Dimensions of piton-type coupling
