Bell 412 - How Does the 'delta hinge' work?

[seafuryfan]

Please can someone explain how the delta hinge works on the tail rotor of the 412?

People say it's to equalise the autorotative forces acting on the blades. When viewed, the hinge mechanism is housed within the tail rotor itself, but this doesn't help me to understand it any more. I also see that the housing onto the spindle is offest by about 30 degrees in plan view compared to the blade line, as I look sideways at the blades. Finally, I was suprised at how little the pitch angle alters when the blades move.

Thanks.