The prior art, as exemplified by U.S. Pat. No. 1,723,147 to Fourethier, Aug. 6, 1929; U.S. Pat. No. 2,275,765 to Hummert et al., Mar. 10, 1942; U.S. Pat. No. 2,724,769 to D'Arbeloff, Nov. 22, 1955; U.S. Pat. No. 4,231,079 to Heminover, Oct. 28, 1980; and U.S. Pat. No. 4,328,533 to Paredes, May 4, 1982 is generally illustrative of the pertinent art. None of the devices shown in the prior art protects the circuitry and appliances from burn out as a result of short circuits and other circuitry failure. Such burnout can be extremely costly when the power pack, connecting cables, and appliances are sophisticated or of a heavy duty nature. Although some effort has been made in the past to use fuses in such circuitry, this has proven to be unsatisfactory in unsafe circumstances where the user may not have the time or be able to change such a fuse. For example, it is especially inconvenient to attempt to change a fuse in total darkness such as might be encountered in mining operations or night sporting activities such as racoon hunting.
Another disadvantage with the prior art is that the power pack is often worn about the waist and suspended at the center of the back. Such positioning can be especially troublesome to persons with lower back problems. Moreover, it is almost impossible to wear such a back centered power pack in an automobile or truck.
USPTO Backgrounds
USPTO Backgrounds