“This is the most stable car transporter I have ever driven,” says driver Neil Fennell.
And fleet engineer Rob Woollett says he likes the “simplicity and low maintenance” features of the Ringfeder draw bar coupling.
Woolett points out that UK car transporter drawbar configurations tend to involve a short prime mover with a long close coupled trailer – designed to optimise the load space within the legal 18.75 metres.
That accommodates a maximum of 11 medium sized saloon cars – seven on the trailer and four on the prime mover – assuming the European four metre height limit is exceeded.
However, the high centre of gravity can give an adverse effect on handling and stability – which is where the Ringfeder 5085 T ball type coupling comes into its own.
Ringfeder’s coupling takes a standard flange bolted 50mm DIN trailer eye and bolts on two half spheres, creating the ball.
The truck end of the coupling system has a mounting plate drilled to the 160 x 100mm draw beam bolting pattern and consists of an upper hinged part and a lower fixed section into which are located two phosphor bronze bearing cups.
The two coupling parts are secured by locking pins. Two 20mm bolts (torqued to 380—420Nm) compress two heavy-duty springs, providing the clamping force on the ball in the phosphor bronze cups.
VBG, in the UK, explains that it is this constant clamping force that dampens the effect of trailer snaking, so also assisting with stability.
There is also no free play, meaning less likelihood of wear between moving components, adds a VBG spokesperson.
