«Previous    Next»
Electric Appliance Lock
Herbert A. Harmison, Jr., an engineering professor at Iowa State University, came up with a way to lock up cords on electrical tools and appliances, both as a way to keep youngsters from using them and to discourage adults from using electrical tools and other equipment without permission.
Harmison says other such devices on the market are extremely complicated. His first model consisted simply of a metal pin welded to a steel washer. The pin slips through the holes in the end of the prongs on the plug and the washer slips over the shank on the lock, making it impossible to use the plug. Harmison has patented the lock and hopes to find a market for it through the Iowa State University Research Foundation.

  Click here to download page story appeared in.

  Click here to read entire issue

To read the rest of this story, download this issue below or click here to register with your account number.
Order the Issue Containing This Story
1984 - Volume #8, Issue #3