Page:The Russell Engine-Four Valve Automatic Cut Off.djvu/7

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Fig. 7 shows section through cylinder and steam chest, and is so plain as to render any explanation almost unnecessary. The piston shows our anti—friction metal band between the packing rings,and the manner of fastening piston to rod also shown. It will be noticed that the piston is screwed on to the rod and that the nut is a jam nut only. The stuffing box shows the gland in place, and it will be noticed that it projects through the Stuffing box nut and receives all the wear of the rod without allowing the latter to come in contact with the nut.

The arrangement of the steam valves is very easily followed out in this cut. The main valve (admission valve it might be called) is triple ported on the side next to the cut-off valve, which enables the cut—off to be accomplished in one-sixth the time required for a single-ported valve. Steam is admitted between the faces of the valves as shown by the open spaces in the cut, and this so reduces the load on the valves as to make them practically balanced. To insure against the possibility of the valves leaving their seats or slamming, the steam chest cover is fitted with the plates and springs as shown, and should the valve slam, the engineer can easily stop this by increasing the compression on these springs through the set screw, from the outside of the chest cover. The cut also shows the stretcher rods by which the two ends of the valves are made adjustable, so that "lead" may be increased or decreased without either resorting to chipping or to moving the eccentric.

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