Street mail boxes are well known and are widely used. At one time they were predominately used in rural areas. However, recent postal regulations have required that new homes have a street mail box positioned along side a roadway. The mail boxes are positioned close enough to the roadway that mail can be placed in them by a mail carrier from his vehicle. Residents with street mail boxes quite often do not know if the mail has been delivered unless their mail carrier has a very strict time schedule or unless they happen to see the mail carrier at the instant the delivery is made. More often than not the resident is required to walk to the mail box and inspect its interior.
There has long been a need for a simple yet convenient device which can effectively signal the mail box owner as to the delivery of mail. Several different mail box signal devices have been devised. Examples of such signal devices can be found in U.S. Pat. Nos. 1,149,781; 1,742,128; 2,782,983; and 2,905,378. A common disadvantage with many of the known mail box signal devices is that they are relatively complex. They easily break or readily become inoperable. A particular problem with known signal devices used in northern climates is that they are prone to not work in freezing rains and snows. Still another drawback with known signal devices is that they are difficult to install on a mail box. Street mail boxes are normally made of sheet metal. Most signal devices require that a number of drill holes be made into the box. The holes must be precisely located or the devices will not attach properly and work properly.
There is still a need for an improved street mail box signal device. Initially such a device must be easy to install. Additionally the device must be easy to operate under a wide variety of weather conditions. Ideally the device will have a minimum number of working components so as to minimize working problems. The device must also be automatic in operation so as to be effective and acceptable.