Patent Application
20080309059
This invention relates generally to vehicle traction enhancing devices, particularly of the ballast weight type for a rear wheel drive vehicle.
Ground vehicles, such as an automobile or a truck, are dependent upon good traction between their tires and the road upon which they are being driven. Traction is a function of the coefficient of friction between the tire and the road on which it travels, and the force (weight) pushing the tire into contact with the road. Maintaining high traction is desirable for control of the vehicle. Traction is maximized when the coefficient of friction and vehicle weight are both high.
Under normal driving conditions, a high coefficient of friction, readily available from the good tire and road materials that are commonly used, leads to satisfactory traction for any given vehicle weight. Since traction is normally satisfactory, vehicle designers try to minimize vehicle weight to achieve several benefits, including improved fuel economy. Throughout the history of automotive travel, vehicles have had to contend with weather conditions such as rain, snow, and ice that reduce the coefficient of friction between the tires and the road, thus making vehicle traction temporarily less than satisfactory. At these times, the often-employed method for enhancing traction is to temporarily increase the weight acting downward on the tires, by making the vehicle heavier. This increased weight is most desirable over the “driven wheels” that have the tires that must transmit the torque of the engine to the road surface.
In many automobiles, such as pickup trucks and rear wheel drive sedans, a storage compartment such as a trunk or a cargo bed sits near the driven wheels. Empty storage compartments such as these are among the lightest areas of the vehicle, so tires located near them have little weight forcing them into contact with the road. However, these compartments do provide an area to which weight, sometimes referred to as ballast, can be temporarily added. Some examples of readily available weights that have been temporarily added include snow, tree stumps, boulders, containers filled with sand or water, and large concrete blocks. These materials, and others, are often placed loosely in the storage compartments.
Drawbacks of these various materials can include difficulty in carrying them to and from the vehicle, storing them when not installed, securing them to prevent movement, and a low weight to volume ratio that causes the storage compartment to be too full to perform its primary function of carrying the goods for which it was intended.
Thus, a need exists for an easy to use high-density, aesthetically pleasing, modular vehicle traction enhancement system that can be installed and removed by people of limited lifting ability. The system should be optimized to consume a minimal amount of the available cargo space.
One embodiment of a vehicle traction enhancement system according to this invention includes an elongate carrier selectively coupled to a bed of a vehicle storage compartment. The system includes a plurality of retention devices spaced along a length of the carrier, and a plurality of weights each selectively retained by one of the retention devices on the carrier. The carrier and associated weights are positioned relative to the driven wheels of the vehicle to increase traction of the vehicle.
Other embodiments of this invention are directed to the system in combination with the vehicle and a method of enhancing vehicle traction.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description of the invention given above, and the detailed description given below, serve to explain the principles of the invention.
To fasten the system 10 to the bed 12, a variety of methods could be used. In this embodiment, mating Velcro™ portions 30a and 30b are shown at one end of the carrier 20, and identical pieces are used on the other end (not shown). Carrier 20 has Velcro™ 30a attached to it by stitching or other methods, and bed 12 has Velcro™ 30b attached by an adhesive or another attaching process. Carrier 20 along with the Velcro™ portions 30a may be installed and removed as needed by mating the portions 30a and 30b together, either when the carrier is loaded with weights 24, or preferably when it is empty so that the person need not lift and work with such a heavy object. Other examples of fastening devices instead of Velcro™ could be nuts and bolts or hooks and eyes.
Optionally, an anti-skid material (not shown), such as textured rubber, could be used under the bottom of the carrier 20 to reduce the loads transmitted to the fastening device 30a and 30b while the vehicle changes speed or direction.
While this invention has been illustrated by the description of one or more embodiments thereof, and while the embodiments have been described in considerable detail, they are not intended to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. For example, the compartments 22 that are depicted in the preceding drawings include sides that are approximately perpendicular to their tops and bottoms. Other embodiments could have the compartment formed from only a top and a bottom material, with appropriate slackness to allow a weight to fit inside. Also, while each of the preceding drawings showed only one carrier 20 installed, the modular nature of the device includes the ability to install these side by side, anywhere they will fit in the storage compartment 14. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and method and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the general inventive concept.
