Title: The Safety Mailbox
America has a long history of the roadside mailbox dating back to the RFD inception in 1896. This new mail service provided for a way for rural and suburban homes to send and receive inexpensive mail. Now 584 million pieces of mail are delivered daily.
As wonderful as roadside mail is, the mailbox can be dangerous to autos and pedestrians. Damaged mailboxes are a nuisance for homeowners and an added cost to municipalities who pay to replace mailboxes damaged by their snowplows.
The Safety Mailbox solves many of those problems. Using standard economy hardware and the power of gravity, it swings away from glancing impacts and resets itself. When run over directly, breakaway bolts minimize damage to the mailbox and the automobile. Gravity provides the centering force so the box swings easily enough not to injure a pedestrian or cyclist who might bump into it.
The vertical posts are constructed from U-Channel signage post. The lower of the two pieces is driven (or cemented) into the ground leaving 4-6 inches above. The upper post is bolted to the lower post with two aluminum shear bolts. A tubular spindle pivots inside eyebolts mounted to the channel. The top beam tips vertically on the spindle. As the beam mounted mailbox swings to the side, the chain on the back limits the travel. As the beam continues to rotate, the chain at its limit, pulls the beam down at the back and the mailbox rises up as it rotates away.
The concept of a swing-away mailbox is not new. The novelty of this design lies in the ease of installation and the low cost robust components. The proven history of the breakaway U-Channel signpost design prevents litigation over the box being a roadside hazard.
The five main components are:
1.) 5/4 x 4x 46” teak wood pre-drilled beam.
2.) 3/8 black pipe welded & galvanized to form the spindle.
3.) Galvanized chain.
4.) Two sections of 2lb/ft. U-Channel sign post.
5.) Mailbox of choice.
The Mailbox assembly can be easily manufactured in almost any shop using a saw , a welder , a drill press and a few hand tools. Because of the two-piece post design and the folding nature, it can be partially assembled and packaged in a small box 4 foot long.
A fast moving snow plow can throw a hundred pounds of wet snow against the mailbox causing it to rotate 270 degrees around, dissipating energy as the mail box gains elevation. The mailbox then swings back to home position afterwards. A normal, rigid wood post assembly, would break with the same snow impact.
The design as shown in this example is not aesthetically pleasing because it shows the bare mechanical nature. To decorate, the U-Channel can be covered with a plastic, metal or wood sleeve. A flag-type sewn cover can be placed over the rear chain to hide the chain as well as decorate.
Leo Honetschlager 6/21/2010
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