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
The net lateral force between coupler and ball is zero. However, since both struts exert a rearward force on the A-frame, the coupler must exert a rearward force on the ball.
Well Ron, we agree half way on this one. There is clearly no net lateral force applied to the coupler by the struts. However I don't think a rearward force is applied either. You are correct when you state that the struts push aft on the a-frame, but at the same time they are applying an equal forward push on the hitch head. Since the coupler is located on the upper element of the hitch head, mounted between the strut attachment points, the two opposing forces cancel out so there is no net force on the coupler in the longitudinal axis. This allows the coupler to provide two functions only. It acts as a "ball joint" in the vertical plane so the A-frame can pivot up and down on uneven road surfaces (e.g., when coming to the bottom of a sloped driveway) and it provides a point to transfer force from the TV along the longitudinal axis during acceleration and deceleration.
The reason I tend to harp on the struts so much is that Hensley states in the installation manual (and I'm paraphrasing) that if the struts are set up incorrectly, you have reduced or no sway control. I think they are an integral part of how this whole system works. And I also think the preload they apply to the hitch head/four bar linkage is an important part of that. I just haven't quite figured out how to put it into a good analytical discussion yet.
Andy
