1. Field of the Invention
The present invention is broadly concerned with improved breakaway sign posts which can be used to support various types of signs in roadway environments. More particularly, the invention is concerned with such sign posts, as well as the coupling assemblies used to interconnect upper and lower sign post sections, wherein a magnetic coupling arrangement is employed in lieu of complex and costly mechanical couplers.
2. Description of the Prior Art
Posts of many different varieties are used in association with roadways. Such posts may be employed to support signs, providing information to vehicle operators, and barriers, directing vehicles away from hazardous areas. Most posts along a roadway are fixed to the ground by digging a post hole, inserting the base of the post into the hole and then filling the hole with concrete or other material to support the post.
Such roadway posts are often inadvertently hit by vehicles traversing the roadways, which usually result in breaking of the posts. When a post breaks, the top portion thereof can rotate toward the vehicle and possibly enter the vehicle's passenger compartment. This can result in serious or even fatal injuries to the occupants.
A further problem with roadway posts currently in use is the difficulty in replacing the post once it has been broken. To reinstall a damaged post, the original concrete must be dug up and removed. Then, a new post is inserted into the hole and fresh concrete is poured to fix it in place. This is labor intensive and requires several man-hours of labor for each broken post.
Breakaway posts have been devised in the past for use in supporting signs, while providing a breakaway function during a sudden vehicle impact. For example, U.S. Pat. No. 6,264,162 describes a successful design of this character. This breakaway post assembly includes a specialized breakaway collar having strategically located lines of weakness which yields during a vehicle impact. Additional breakaway post designs are described in the following U.S. Pat. Nos. 5,480,121, 3,349,531, 3,820,960, 3,846,030, 4,490,062, 4,926,592, 4,928,446, 5,088,683, 5,160,111, 5,214,886, 5,484,217, 5,535,555, 5,782,040, and 5,988,598.
These prior art breakaway posts are all characterized by mechanical connection structure between upper and lower separate post sections. While providing a useful breakaway function, once impacted by a vehicle, it is necessary to reinstall the collar or related structure to put the post back into an operative condition. Moreover, in certain of the prior designs, it is impossible to repair the breakaway post, and a new installation is necessary. In other instances, the prior breakaway posts do not break away in any predetermined fashion or direction, i.e., it is possible that the broken away portion may fall toward the vehicle rather than away from it.
There is accordingly a real and unsatisfied need in the art for an improved breakaway post assembly which avoids complex mechanical collar arrangements and permits easy repair of a post after it has broken away, and which is designed to cause the broken away post section to fall in a predetermined direction away from the impacting vehicle.