US723052A - Collapsible piston-valve. - Google Patents

Description

No. 723,052. PATENTED MAR. 17, 1903.

W. G. SINNAMON. GOLLAPSIBLE PISTON VALVE. APPLICATION FILEI? NOV. 15, 1902.

N0 MODEL.

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UNITED STATES PATENT FFICE.

WILLIAMG. SINNAMON, OF SYRACUSE, NEW YORK.

COLLAPSIBLE. PISTON-VALVE.

SPECIFICATION forming part of Letters Patent No. 723,052, dated. March 1'7, 1903.

Application filed November 15, 1902. $erial No. 131,559. (No model.)

T at whom, it may concern.-

Be it known that I, WILLIAM G. SINNAMON, a citizen of the United States, residing at Syracuse, in the county of Onondaga and State of 5 New York, have invented certain new and useful Improvements in Collapsible Piston- Valves; and I do hereby declare the following to be a full, clear, and exact description of the invention, suchas will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in piston-valves for steam-engines,whereby they are made collapsible under sudden emergencies, as of water in the cylinder, where the relief-valves, if any, refuse to work, compelling some portion of the engine to give way 7 unless otherwise safeguarded. In slowrunning slide-valve engines the difficulty does not occur, as the valve will lift off from its seat and permit the water to escape by way of the steam-chest; butin high-speed engines the blow is too sudden for reliance on such a mode of relief, and with piston-valves,which z 5 are well adapted to high-speed engines, even this relief is impossible, since they are solid l and constrained on all sides by a surrounding chest or casing.

repairs necessitated by this state of things renders some remedy in construction highly desirable, and this I have accomplished in the improvement about to be described.

In the drawings formingapart of this specification, Figure 1 is a side view of the bushing of a cylindrical valve-chest. Fig. 2 isa transverse section of i the same on line' 2 2 of Fig. 1. Fig. 3 is a transverse section of the piston on line 3 3 of Fig. 4. Fig. 4 is a longitudinal section of the piston on line i 4 of 0 Fig. 3. Fig. 5 is a front view of the yoke or pulling-plate of the piston-valve.

b is the bushing of a bored valve-chest, showing the necessary outlet and inlet passages or ports for steam. The bushing is entire at the points 0 d to cover the apertures in the collapsing piston. e

e e are the members of the collapsing piston separated longitudinally by a space sufficient to allow of the requisite play. These valve members, recessed externally in the usual manner to permit the passage of steam from port to port, are ordinarily held against The frequent and costlytheir seats by the steam-pressure in the valvechest, and two or more light springs, which may be spiral springs f f, as shown, are provided to maintain them in position when there is no pressure in the valve-chest. The

valves e e are movably connected together by a tie-pieceg, of I shape in section, with flanged or expanded heads playing in recesses 41 2', formed in the valve members 6 e. Said tie-piece thus allows the said valve members to collapse on occasion, as from water in the cylinder, while preventing them from separating beyond the limit formed by the expanded heads occupying the recesses 41 2'.

h h are perforations in the tie-piece to contain the springs f f. The tie-piece has two feet or projections j j, which rest on lugs ZZ, formed .on the valve members e e, and removable clamp-pieces k are provided atthe other extremity of the piston to prevent the tie-piece g from coming out, while permitting free play to the valve-pieces e e.

.m is a yoke or pulling-plate removably secured to the valve members of the piston by bolts or other suitable means passing through elongated apertures or slots n n in the said yoke, which permit the valves to collapse. The valve-rod 0 is centrally secured to the yoke m. It is obvious that if but one of the valve members is collapsible the result is the samein a degree.

Itis not indispensable that the valve-chest be cylindrical. If the chest is bored, which is the simplest construction mechanically, the valve members 6 e constitute a cylinder when fully expanded to fit the chest; but if the chest has plane surfaces the valve members of course should be plane accordingly.

To insure a steam-tight and perfectly-balanced valve, the following method of construction is preferably adopted: The two valve sections or members 6 e are immovably secured on a tie-piece which is four onethousandths of an inch smaller in dimensions between the flanges s 3 than the standard tiepiece with which the valves are designed to work. The piston is then placed in the lathe and accurately turned or planed to fit the valve-chest. The standard tie-piece is then substituted for the temporary one, which allows the valve to expand four one-thousandths of an inch within the valve-chest,

permitting the valve and valve-seat to Wear smooth and remove the tool-marks in both. When after a few days wear the valve members and seat have thus become surfaced together, there will be neither appreciable friction nor leakage, and the valve will remain tight indefinitely. To take up the wear, itis only necessary to remove the clamp-pieces 70 It and pull out the tie-piece, when a few strokes of a file along the inner edges of the flanges s s Will remove sufficient stock to permit the valves to expand enough to compensate for the accomplished wear.

The advantages possessed by this valve over the piston-valves in common use are that it collapses and relieves the cylinder of any charge of water, thus making reliefvalves an auxiliary instead of a necessity. It is steam-tight and will remain so for a long time. On account of the absence of rings the ports will not be gouged out. Leakage may be taken up without removing the valve from the chest or disturbing adjustments. As but two bridges are used,it will not wiredraw the steam. It is practically frictionless and perfectly balanced at all times. The tiepiece should be so proportioned that the wear on the face of the valves is compensated as nearly as possible by the wear on the inner edges of the flanges s s, so that the necessity for letting out the valve to prevent leakage is a rare occurrence.

I claim and desire to secure by Letters Patent- 1. A piston-valve formed of diametrically degree of separation to the normal diameter of the piston, while permitting their approximation, and a pulling-plate to which the said collapsible portions are movably attached, substantially as specified.

4. In a piston-valve, a piston having movable valve members ot semicylindrical contour suitably recessed externally, normally separated by a suitable interval, internal recesses 11 i in said valve members, and a tiepiece with expanded heads playing in said recesses 71 1 whereby the valve members are restrained from expansion beyond the diametral limit of the piston While allowed to collapse to permit the discharge of any abnormal liquid present in the steam-cylinder, substantially as specified.

In testimony whereof I affix my signature in presence of two witnesses.

WILLIAM G. SINNAMON. Witnesses:

JNo. P. CROWELL, N. J. LINDENMEYER.

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