Hensley Arrow: How does it REALLY work?
There have been several discussions on this hitch that have become somewhat 'controversial'. I am NOT trying to stir this controversy/bashing back up. Instead, I'd like to see a good, intelligent di...
Forum Discussion
willald wrote:
I would submit, that Tim is right in that pivoting does take place from both ends. However, due to the way the pivot point is projected, it is VERY difficult (almost impossible) for the trailer to initiate much pivoting at all through that pivot point/elliptical path.
So in essence, from the trailer's perspective, it cannot pivot. Or, the pivoting it DOES do, since it pivots through the virtual pivot point/elliptical path we have outlined, is pivoting that does not affect the tow vehicle at all, so it basically eliminates all swaying as we know it.
How does this sound? Can we all agree on this? Or, am I over-simplifying it too much? :)
Will
Will, I think we're talking about two different kinds of "pivoting". On the one hand, we're talking about the TT swinging behind the TV, which it is free to do if there is no lateral force acting on the TT's tires. OTOH, we're talking about the TT initiating pivoting of the TV.
When we're talking about the TT "initiating pivoting", we should be referring to the ability of TT-induced lateral force to cause the TV to tend to pivot about its rear axle. In this second case, the HA significantly reduces the TT's ability to initiate pivoting.
In the first case, the HA does not prevent the TT from swinging behind the TV. It is the TT's tires which control the amount of swing. The HA does not allow the TT to pivot at the ball coupler. But, the HA's linkage does allow the TT to move as though the TT were pivoting about the VPP (or about the effective pivot point as the Hensley Patent Document refers to it).
So, from the TT's perspective, it CAN pivot. However, the lateral loading on the TV, which is a separate issue, is reduced by the HA. And, the HA causes the point of application of the lateral load to be moved closer to the TV's rear axle. The net effect is to significantly reduce the "steering moment" on the TV. The HA does not have to eliminate the swinging of the TT in order to reduce the loading on the TV. The HA controls the magnitude of the "steering moment" and the TT's tires control the magnitude of the swinging.
Ron
