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66. The Atomizing Sprayer.—This type of sprayer consists of a cylindrical tank or reservoir in which is soldered a small tube that reaches nearly to the bottom of the tank. Upon this tank is mounted a pump, having a nozzle in the form of a scalene cone, and with a relatively small orifice. The small tube is placed in the tank in such a manner that its top is directly in front of, and on a level with, the center of the orifice of the pump. When a stream of air is expelled from the pump, it creates a partial vacuum in the tube, causing the liquid to rise. When the liquid encounters the stream of air flowing from the pump, it is broken up into a fine spray.

The Elevation (Fig. 199).—A circle 4 in. in diameter is first drawn to represent the end of the reservoir. The elevation of the pump barrel is drawn next, placing it in a horizontal position and tangent to the reservoir. The following are next drawn in order: (1) The pump rod assembly; (2) the -inch diameter tube in its proper location; (3) the wooden plug that guides the pump rod; (4) the brace, according to the dimensions given.

Pattern of Conical Nozzle (Fig. 200).—The elevation of the cone is reproduced and a half-profile attached directly to the base. This half-profile is divided into four equal parts. The shortest distance from the base to the apex is the line from point 1. Therefore, with point 1 as a center, arcs are drawn from points 2, 3, and 4 of the half-profile, cutting the base of the cone as shown in Fig. 200. With the apex as a center, arcs are drawn from each intersection of the base of the cone. Any point on the arc from point 1 is selected and is connected with the apex. This line will serve as the starting line of the pattern. The compass is set equal to the distance between any two divisions of the half-profile. Starting from point 1 of the pattern, point 2 is found by drawing an arc (with the compass as already set) that intersects the arc drawn from the second intersection of the base line of the cone. In like manner points 3, 4, and 5 can be located. A straight line from point 5 to the apex will give the half pattern. Since both halves are exactly equal, the other half may now be drawn by reversing the process already described. A ¼-inch lap should be added to one side of the pattern.