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Title: |
1890 Article-Ball Engine Co., Automatic Cut-Off Steam Engine |
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Source: |
The Steam User 1890 pgs 16-19 |
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Insert Date: |
4/14/2011 9:42:25 AM |
The requirements of a high-speed engine, to ensure good results for the class of work they are now used, require of course a perfect governor. To obtain an almost even speed under both variable load and steam pressure is a very difficult problem, and a description of the method in accomplishing this, as used in the Ball Engine, an illustration of which is on the opposite page, will be of interest to engineers.
The governor is placed in one of the driving-wheels, and the details of construction may be understood by reference to Figs. 3 and 4. In Fig. 4 may be seen the eccentric A, with the arm B, which is pivoted at its outer end to an arm of the wheel. This eccentric has an elongated shaft opening, and is swung across the shaft by another eccentric in the side of disc C, which disc or intermediate is operated by the centrifugal weights.
Fig. 3 illustrates the wheel containing the weights and springs, and also the dash-pot and spring, which is the distinctive feature of the governor, and is the means of producing the results peculiar to this engine.
By this arrangement it is possible to adjust the governor so that the engine shall run exactly the same speed, whether leveled or not, and the speed will not be affected by changes of boiler pressure.
The theory of this governor is fully explained in the descriptive catalogue of the engine.
Although the governor is distinctively the feature of the engine, they have endeavored to combine other desirable features, which will commend themselves to the purchasers of engines. Prominent among these is the valve, which by its construction ensures a high grade of economy through a long period of time, and, compared with the piston-valves so commonly used in this type of engines, is often a matter of even greater importance than the more perfect regulation.
Figs. 5, 6, 7, 8, and 9 give a very good idea of the construction and operation of the valve. It will be seen that the valve is in two parts, which are connected by telescopic sleeves, which allow each half to adjust itself to its seat. Steam passes directly into the valve from the boiler in every position, and is distributed to either end of the cylinder by the position of valve.
Similar ports are placed directly opposite these in the upper part of the steam-chest, thus making valve double ported. The exhaust takes place over the ends of valve and into steam-chest, which is always filled with exhaust steam, and is in direct communication with exhaust pipe through openings in the lower corner of steam-chest at each end. Each half of valve is held in contact with its seat by direct steam pressure, and the wear is thus followed up.
Figs. 7, 8, and 9 are views of the valve.
The sleeves are made of a size that will just give sufficient pressure against each valve seat to ensure good contact.
It must be admitted that no better or more serviceable valve has ever been devised, and its superiority over any form of piston-valve is too obvious to be questioned. It is very common for the builders of piston-valve engines to undertake to overcome the "prejudice," as they call it, against that form of valve. Our valve needs no defense or apology.
Another feature is the opportunity to inspect the valve when in operation under boiler pressure by removing the steam-chest cover, thus enabling the engineer to detect any leakage and scrape the surfaces until absolutely tight.
Fig. 10, which is a sectional view through the centre of this engine,
fives a very good idea of the details of construction. (Manufactured by the Ball Engine Co., Erie, Pa.) |
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1890 Ball Engine Co., Automatic Cut-Off Steam Engine
1890 Ball Engine Co., Automatic Cut-Off Steam Engine (Governor & Valves)
1890 Ball Engine Co., Automatic Cut-Off Steam Engine (Sectional View)
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