US1940376A - Water column for steam boilers - Google Patents

Description

Dec. 19, 1933. G. w. STETSON 1,940,376

WATER COLUMN FOR STEAM BOILERS Filed Dec. 27, 1930 .Elql

Q Q I 10 II iineJJ Jzvenior q xv- {Mew Kiwi} Patented Dec. 19, 1931;

George W. Stetson, Hingham, Mass.

Application December 27, 1930 Serial No. 505,101

1 Claim.

The present invention relates to liquid columns for pressure vessels, and more particularly to a water column for steam boilers embodying a high and low water alarm.

The purpose and object of the present invention is to provide an exceedingly simple and eflicient form of high and low water alarm which is sensitive to changes in water level and free from structural complications which might conceivably interfere with the continued operation of the device.

With this and other objects in view, the various features of the invention consists in certain novel features of construction, combinations and arrangements of parts hereinafter described and claimed, the advantages of which will be obvious to those skilled in the art from the following description.

In the accompanying drawing illustrating the preferred form of the invention, Fig. 1 represents a section in elevation of my improved form of water column, and Fig. 2 is a detail illus trating a slightly modified form of float construction with provision for guiding the operating rods.

As illustrated more particularly in the drawing, the liquid column comprises a cast or drawn metal tube 10 having an integrally closed bottom portion 12, and flanged outwardly at the upper portion 14 to receive a cover 16. Mounted in-the cover is a whistle 18, having the usual valve seat 20 communicating therewith. Supported on the under side of the cover 16 is a forked support22, threaded into the cover at 24, and having a pivot bearing 26 for an operating lever 28. Mounted upon the lever at one side of the pivot is an operating valve 30 adapted to engage with and close on the valve seat 20 when the water level is maintained within normal operating limits. Connected to the opposite ends of the operating lever 28 are depending rods 32 and 33, which extend downwardly from the lever as far as necessary throughout the length of the column. Each of these links is provided with a knocker, these knockers or adjustable stops being indicated respectively at 35 and 36, and disposed in such a manner that upon upward movement of the knocker 36 due to a rising water level, or downward movement of the knocker 35 due to a falling water level, the lever v sirable elevations of water level are accomplished by a single float 40 of generally cylindrical outline, and having upper and lower heads 42 and 44 secured therein in a manner to hermetically seal the interior of the float. Although not essential, the float may desirably be made of stainless steel and the heads of the same material welded thereto. Such a float is well suited for my purpose, as it successfully resists erosion and is capable of withstanding the pressures on the order of those encountered within the column. 7

The cylindrical float, which fits loosely within the shell of the column and is capable of a rising or falling movement therein, is preferably provided with two guide tubes 46 and 48, sealed into the ends of the float in a manner to avoid communication between the interior of the float and the interior of the guide tubes. The rods, which are substantially smaller in diameter than the interior of the tubes, slide freely therethrough, and with this construction it will be evident that the tubes serve as elongated loose guides to preserve the proper alignment and parallelism of the operating rods 32 and 33. These tubes can conveniently serve as guides due to the fact that the cylindrical float conforms generally to the interior of the water column and is constrained against substantial lateral movement or other than the vertical movement, due to the rising and falling of the water level.

With this construction the hollow float, due to its bouyancy, rides upon the water in the column at a level corresponding to its weight and bouyancy; the operating rods pass freely therethrough, and the only weight upon the pivot bearing and operating parts is that due to the lever and connected rods with their individualknockers. Accordingly, the pivot bearing is relieved from any substantial weight with accompanying friction due to such weight and resulting wear. This is of major importance in apparatus, of this character where the moving parts are surrounded by' corrosive vapor at high temperatures and cannot be given frequent and regular attention. Due to the fact that the weight upon the operating parts is reduced to a minimum, the entire bouyancy of the float can be utilized, as an effective operating load for opening the valve upon abnormal rise or fall of the water level. Fig. 2 illustrates a slight modification of Fig. 1, in which the float shown in Fig. 1, instead of being provided with guide tubes, has guiding lugs 50 and 52 at opposite sides of the top and bottom, which are notched or grooved to engage operating rods and guide the same. V

below the float, a single hermetically sealed float within the casing corresponding generally in contour to the interior of the casing, guiding means upon the float engaging with each operating rod throughout the entire movement of the float for preserving general parallelism of the rods through engagement with the casing, and a stop member connected to each rod above and below -the flo'tit, respectively, to causemovement of "the ro dsin opposite direction upon predeter- 'minedrising and falling movements of the float.

GEORGE W. STETSON.

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