A constant levelling device for an atomizer type sprayer


Material Information

A constant levelling device for an atomizer type sprayer
Physical Description:
2, 2 p. : ill. ; 27 cm.
Fulton, Robert A
Henderson, Charles F
United States -- Bureau of Entomology and Plant Quarantine
U.S. Department of Agriculture, Bureau of Entomology and Plant Quarantine
Place of Publication:
Washington, D.C
Publication Date:


Subjects / Keywords:
Spraying equipment   ( lcsh )
federal government publication   ( marcgt )
non-fiction   ( marcgt )


General Note:
Caption title.
General Note:
General Note:
"October 1942."
Statement of Responsibility:
by Robert A. Fulton and Charles F. Henderson.

Record Information

Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 030351626
oclc - 781856452
System ID:

Full Text

October 1942

United States Department of Agriculture
Agricultural Research Administration
Bureau of Entomology and Plant Quarantine


By Robert A. Fulton, Divisiojn of Insecticide Investigations, and
Charles F. Henderson, Division of Foreign Farasite Introduction

In laboratory tests with parasites of the black scale it was
found that the atomizer type of gun with a suction feed would not
deliver the spray at a uniform rate unless the liquid in the supply
vessel was maintained at a constant level. It was also found that
the rate cf delivery would alter the type Gf deposit on a lemon sur-
face. As it was necessary to standardize the procedure, a device was
developed to maintain the liquid at a constant level in the supply
vessel. The unit described herein was designed for water-soluble

The spray gun employed was of the atomizer type with a suction
feed similar to the one commonly used in lacquer application. As the
atomizer requires a large volume of air, it was found necessary to
use a large diaphragm reducing valve. This type of valve is commonly
used by gas companies in rural service. It will maintain a constant
pressure for different rates of delivery, thus eliminating the necessity
for readjustment.

The constant levelling device is shown diagrammatically in
figure 1, and a general view of the combined units is shown in figure
2. It consists essentially of a reservoir inverted in the spray
vessel. The level of the liquid is maintained in the spray vessel
by displacement from the reservoir. In the construction of the reser-
voir it is necessary to use a large tube to obtain a steady flow of the
spray solution. The tube is cut approximately 10 degrees off the hori-
zontal to permit a small amount of air to enter the tube.

A flat 8-ounce bottle (A, fig. 1) was used for the reservoir.
to permit it to be close-coupled to the spray vessel. With this
arrangement, variation of the liquid level in the spray vessel when



bubbles of air enter the reservoir through the connection tube is
minimized. A brass tube (D), three-fourths of an inch outside diame-
ter, was soldered to the screw cap of the bottle (B). It was 3-1/2
inches long, with the lower end cut at approximately 10 degrees off
the surface of the liquid. A brass collar (C), approximately three-
fourths of an inch inside diameter and 1 inch high, was soldered to
the cap of the spray vessel. The collar supports the reservoir
bottle in a fixed position. The atomizer is connected to the spray
vessel by means of a compression nut (E).

In operating the device the reservoir containing the spray
solution is inverted in the lid of the spray vessel. As soon as the
liquid in the spray vessel has reached as high as the bottom of the
tube a constant level will be maintained for the application.

Figure 1.--Details of construction of the constant levelling
device. A, Reservoir; B, screw cap; C, brass collar;
D, brass tube; E, compression nut.

Figure 2.--General view of the spraying apparatus.


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