A New Door Opener.
Walter Bouse, an engineer in the Seattle (Wash.) Fire Department, has patented a new door opener. The Bragg patent for opening the doors expired last February, and, although Bouse had received word from the patent office that his contrivance was not an infringement. Corporation Counsel Donworth thought best to wait until the law had settled the matter conclusively . By the Bragg machine the doors were opened after the first tap on the bell, but by House’s contrivance the doors are opened on the back stroke of the hammer and the horses are coming out of the stalls before the firemen or people in the city have heard the first sound of the bell.
At first glance House’s door opener looks complicated, but on close examination the operation appears very simple. A long brass lever runs under the gong of the indicator on the main floor, and the hidden end is so adjusted that the sounding hammer, when thrown back for the first stroke, hits the end and moves it about an eighth of an inch. At the door end of the lever is a rod which runs down at right angles and holds in place another lever running parallel to the one first mentioned by a one-sixteenth of an inch catch. Four inches beyond the fulcrum the last mentioned lever is connected permanently with a long rod, which has a heavy weight attached to the lower end and at the upper end, a little below the level of the tops of the doors, are iron arms which look like a “V.” These arms connect with brass rods that run along over the tops of the doors and are in turn connected with the spring which keeps the doors closed.
When an alarm comes in the hammer of the gong is thrown back before it makes a forward stroke and sounds. In going back it strikes the concealed end of the first-mentioned lever and moves it about an eighth of an inch. This motion is transmitted to the lever holding the “ parallel lever ” in place, with the result that the sixteenth-inch connection is broken and the heavy weight attacned to the long rod drops to the floor, pulling the wires that run over the tops of the doors either way toward a common point. The motion of the last mentioned rods is communicated to swing pulleys that draw up the door springs and let the doors fly open.