Ball Couplings
Ball Couplings transmit torque with the balls fitted in between a groove of the outer hub and indentations of the inner hub. They are especially capable of absorbing end play and angular misalignment. Double typed couplings further offer excellent tolerance to large parallel misalignment.The ball coupling forms the connection between towing vehicle and trailer.
An on-road BALL COUPLING has limited movement & therefore is not generally suited to off-road use. This diagram on left shows the limited vertical movement. Major trouble can develop with this type of coupling off-road if the tongue bottoms out into the hitches casting & breaks a piece out of the coupling, rendering it useless. Ball couplings as shown right with hydraulic over-rider brakes have a 360 degree swivel sideways.
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