Anti-sway trailer hitch devices

#Because a typical trailer hitch couples a trailer to a towing vehicle at a spot behind the rear axle of the towing vehicle, any substantial (or even slight) lateral movement of the forward end of the towed trailer can result in simultaneous lateral shifting of the forward end of the towing vehicle. Lateral movement in the trailer that is not induced by the operator of the towing vehicle can be exceedingly dangerous. Such lateral movement might be caused by, for example, the impact of a strong crosswind on a trailer having a large side cross-sectional area. Similar dangerous movements may be caused by a slipstream impact from a large passing vehicle. These effects can be exacerbated if the trailer is not properly loaded, such as when the center of gravity of a trailer load is disposed forward of the wheels of the trailer and a substantial proportion of its mass rests on the hitch.

#Trailer hitches having no anti-sway function provide no resistance to lateral loads induced by trailer movement. Trailer hitches having an anti-sway function provide some resistance to lateral loads, but known hitches do not have the capability to actively correct sway. Known devices also are not capable of automatically releasing anti-sway corrective forces when they are no longer needed, such as when a user maneuvers a towing vehicle and a trailer in tight spaces and lateral movements of the trailer are desired.

#FIG. 1 is a schematic view showing typical sway of a trailer attached to a first hitch on a towing vehicle, where the hitch provides minimal resistance to lateral loads.

#FIG. 2 is a schematic view showing typical sway of a trailer attached to a second hitch on a towing vehicle, where the hitch provides enhanced resistance to lateral loads.

#FIG. 3 is a schematic view showing typical sway of a trailer attached to an anti-sway trailer hitch device on a towing vehicle, according to aspects of the present disclosure.

#FIGS. 1-3 show the general benefits of using an anti-sway trailer hitch device of the present disclosure with a towing vehicle 10 coupled to a trailer 12. FIGS. 1-3 show that a towing vehicle 10 and a trailer 12 may be in a coupled relationship as the combined vehicle travels down a roadway. FIGS. 1-3 also show that a large passing vehicle 14 (or a substantial crosswind) may cause the trailer to undergo a series of oscillations behind the towing vehicle.

#FIG. 1 shows that a typical, unmodified trailer hitch 16 may not prevent or correct a sway motion of a trailer once it is influenced by a disruptive force. In the top panel a vehicle and trailer (a combined vehicle) travel, undisturbed, in a straight line in a traffic lane, along what can be described as the combined vehicle's axis of travel 11. Travel axis 11 of the combined vehicle generally will be coincident with the travel axis 15 of the vehicle 10.

#In the middle panel, the trailer's movement may be disrupted by a sideways force, such as a crosswind or (as illustrated) the aerodynamic force of a large passing vehicle. As indicated, the trailer may be pulled into a vortex in the slipstream of the large vehicle, causing the trailer to drift to one side of its lane, potentially pulling the towing vehicle with it. Angle α1 represents the angle formed between the trailer's travel axis 13 and the combined vehicle's original axis of travel 11 upon initial disruption of the trailer's travel. In the bottom panel, the large vehicle having passed (or the crosswind having ceased), the trailer is no longer pulled to one side of its traffic lane and the towing vehicle attempts to pull it back into the center of the lane. Movement of the trailer back toward the center of the lane is unrestricted, however, and the trailer will continue past the center of the lane and move to the second side of its lane. Angle α2 represents the angle formed between the trailer's travel axis 13 and the combined vehicle's original axis of travel 11 when the trailer swings back. This “whipsawing” or oscillating motion, where α1 and α2 may be similar to each other and which may both be relatively large (especially as compared to the angles shown in FIGS. 2 and 3), is potentially quite hazardous and is not dampened by a standard trailer hitch.