US1172337A - Piston and packing relief-valve. - Google Patents

Description

JOSEPH F. BATTY, 0F BALTIMORE, MARYLAND.

PISTON ANDV PACKING RELIEF-VALVE;

Specication of Letters Patent.

Patented Feb. 22, 1916.

Application flied January 16, 1915. Serial No. 2,557.

To all whom it may concern.'

Be it known that I, JOSEPH F. BATTY, a citizen of the United States, residing at Baltimore, State of Maryland, have invented certain new and useful Improvements in Pistons and Packing Rellef-Valves, of which the following is a specification.

This invention relates to pistons and automatically pressure operated floating valves for relieving the piston packing rings of all steam pressure due to the steam, under high pressure, working in between the rings and their grooves, and is intended Primarily for use with steam engines, though capable of use in other arts.

Heretofore it has been common practice to use either steam pressure packing, wherein in some instances means for reducing the pressure behind the packing below that of the steam in the cylinder have been provided, or to use spring snap packing rings, or other means.

In actual practice I have found that steam pressure packing causes undue friction, requiring excessive use of expensive lubricants, reducing the eiiciency or power of the engine, and causing unnecessary expense in frequent repair, aside from the initial expense of such pistons. I prefer therefore the usual automatically wear compensating spring snag ring packing, but find, as used with the common piston and steam under high pressure, that the latter will invariably work its way in behind the packing rings, forcing them to expand by such pressure and cause the conditions above mentioned with regard to steam pressure packing to such an extent that after but little operation of the engine it is necessary to replace the packing as be1ng too badly worn. Beside being damaging to the rings it is of course damaging to the cylinder, wearing this out before its time.

- The object of this invention therefore is to provide means for automatically permitting the escape of all steam which may work its way behind the piston rings from the charging or working side of the piston to the exhausting side, said means being automatically operated by the compression of the residuum of the exhaust as the piston approaches the end of the cylinder.

To this end my invention consists in the construction, combination and arrangement of parts hereinafter more particularly set forth and claimed.

In the accompanying drawingsz'Figure l is a longitudinal sectional view through the cylinder showing a` piston embodying my lnventlon, partly in elevation and'partly in section to illustrate the position of the pis- 4A indicates the cylinder provided with supply and exhaust ports and slide valve B, and C indicates the piston rod, all as usual, on which is mounted piston member 1 in any suitable and usual manner as shown.

On member lis slipped the concentric member 2 having a. horizontal annular part provided with perforations 3 through which bolts 4 are turned into registering internally screw-threaded bolt holes provided for this purpose in member 1. Piston member 2 also has an annular part fitting around a reduced part of member 1 and provided with annular packing ring channels or grooves 5 receiving spring snap packing rings 6 and radial bores or conduits 7 communicating with said channels extend therefrom to the inner face of said member 2.

Member l is provided at equi-distant points on a circle on both its upper and lower faces with conical recesses 8 communieating with each other by means of a straight cylindrical bore 9 passing vertically through the piston and is also further provided with radial conduits 10 extending from said bores 9 to and registering with their respective radial bores or conduits 7 in the member 2, thus each set of radial bores or conduits l0 and 7 forms communication between one piston ring 'groove or channel 6 and their respective bore 9..- It is tobe understood of course that for each bore 9 there will be as many radial bores or conduits l0 and 7 as there are packing ring channels or grooves 6, but two being shown in the present instance by way of illustration, this being the number commonly provided the usual pistons of steam engines for ordinary purposes. Also, it will be unrin derstood that this invention may be applied to any form of piston having spring snap packing or other 1non-steam pressure pac ng.

Working in each bore 9 is a valve stem 11 square in cross-section with rounded corners to give a good clearance passage for the escaping steam and having its ends cylindrical and externally screw-threaded to receive' the internally screw-threaded valves 12, corresponding in size and shape to the recesses -haust side of the piston and the other valve 12 will always berseated on the pressure side of the piston, excepting during the, very slight interval when they are shifting positions toward the end of the stroke of the piston.

All parts above described may be made of any suitable metal or other material, monel metal being preferred for the valves 12.

In operation, the piston having passed its neutral point and advancing, simultaneously with the shifting of the slide valve to lsupply a new charge, compresses the i'esiduum of the exhaust invariably left in the end of the cylinder and this in compressing acts on the ends of valves 12 on that side ofthe piston, seating them and through the stems 11. unseating the valves' 12 on the now exhausting side of the piston, this action takingYV place just in advance of the entrance of the -new charge of steam into the cylinder. Any of this new charge which works behind the packing rings 6 into grooves 5 may now pass out through radial bores or conduits 7 and 10 to bore 9 and out on the exhaust side of the piston, yas indicated by the solid line arrows in Figli, until the end of the stroke is reached, when the above action will be repeated, any steam working behind the packing now passing out in the direction indicated by the dotted arrows in Fig. 1, and so on, the positions of the valves 12 being reversed at the end of each stroke by compression of the residuum of the exhaust just prior to the admission of the new charge.

This invention has been described throughout asapplied to a vertically reciprocating piston, but of course may be applied to a pistonworking in any plane. Also, it is obvious that various changes and modifications rnay be made in the arrangement, construction, position and shape oi? the several v conduit formin parts, bores and, conduits ofrny invention, of which only the preferred form has been illustrated and described herein, without departing from the spirit thereof, and it is my intention and desire to include all such in the following claims.

Having thus described my invention, what I claim as new and desire to secure b v Letters Patent is':

l. A piston provided with a bore passing therethrough, a packing ring groove anda communication between said groove and ore, in combination with a valve stem working in said bore and a valve mounted on each end of said stem to automatically by compression alternately open communication between said groove and the space on the exhaust side of said piston, and close communication between said groove and the, space on'the compression side of said piston.

2. A piston provided with a bore passing therethrough, packing ring grooves andfconduits forming communication between each groove and the bore, in combination with a valve stem working in said bore and a valve mounted on each end of said stem to automatically open and close communication between said grooves and the space on each side of said piston, the seating faces of said valves being presented toward each other.

3. A piston provided with bores passing therethrough in the direction of travel theref, annular packing ring grooves and radial conduits forming communication between the respective bores and the grooves, in conibination with a valve stem working in each bore and valves mounted on each end 1respectivelyA of said stem to alternately open,

exhaust side when closed on the compression side.

4. A piston provided on each exterior face with registering recesses, bores forming com munication between each two registering recesses, grooves to receive packing and further provided with conduits forming communication between the respective bores and said grooves, in combination with a valve stern working in each respective bore and a valve fixedly secured to each respective end of said stem, said valves corresponding in size and shape to said recesses and the portion of each stem` between its valves being greater in length than its respective bore. l,

5. A cylinder, a piston working therein and provided on each exterior face with conical registering recesses, cylindrical bores in combination With packing rings fitting in said grooves, a valve stem approximately angular in cross-section Working in each .respective bore and a conical valve screwed on the respective ends of said stem andfitting said recesses, the Walls of which act as seats therefor, the portion of each stem between its valves being greater in length than its respective bore.,

6. A piston having longitudinal bores, packing grooves and passages connecting said grooves and bores, in combination with floating valves working in said bores, and, by the compression of the residuum of the exhaust steam, automatically shifted a short distance tovopen the valves on the exhaust side of the piston.

7. A piston having longitudinal bores,

packing grooves and passag'esconnecting said grooves and bores, vin combination with a valve-stem Working in each of said bores and valves mounted on the ends thereof and,

by the compression of the residuum of the exhaust steam,automatically shifted a distance, not exceeding a sixteenth of an inch, to open the valves on the exhaust side of the piston.

In testimony whereof, I have signed my name to this specification in the presence of the subscribing Witnesses. s

JOSEPH F. BATTY.

Witnesses: y

LIzZIE S. BARRON, J. W. MANNING, CHARLES JoRss.

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