US365927A - Balanced valve - Google Patents

Description

2 Sheets-Sheet 1.

(No Model.)

W. W. LEWIS. BALANCED VALVE.

Patented July 5 E a & @1 V D m N/ a Ema 4% P KL I [NI/EN TOR CD13. A TTbRNE Y W] T NESSES (N0 Modgl.) 2 Sheets-Sheet 2.

W. W. LEWIS.

BALANOED VALVE.

No. 365,927. Patented July 5, 1887.

III

Ill/I FFlCE-i XVILLIAM W. LEWIS, OF CINCINNATI, OHIO.

BALANCED VALVE.

SPECIFICATION forming part of Letters Patent No. 365,927 dated July 5, 1887.

Application filed March 1Q, 1886. Serial No. 194,955. (No model.)

To aZZ whom it may concern.-

Be it known that I, WILLIAM W. LnwIs, a citizen of the United States, residing at Our cinnati, Ohio, have invented new and useful Improvements in Balanced Valves, of which the following is a specification.

My invention relates to that class of balanced valves for steam-engines in whicha balancing-plate is employed resting upon and forming a sliding joint with the back of the valve to exclude the steam therefrom; and it consists in the various features of improvement hereinafter more fully described, some of which may be used independently, but all contributing to render the action of the valve more perfect and efficient and relieve the wear of parts, and consequently enhancing durability.

Mechanism embodying myinvention isillustratcd in the accompanying drawings, in wl1ich-- Figure 1 is a vertical longitudinal section of a steam-chest, valve, and balancing-cylinder, showing an adjustable stuffing-box joint for the passage of the plate-supporting rod through the steam-chest cover, and an adjustable lever-connection for between the plate and balancing-cylinder, exterior to the chest. Fig. 2 is a plan view of the same complete, part of the steam-chest cover being broken away to show the valve construction. Fig. 3 is a vertical longitudinal section of a steamchest and valve, showing other details of my invention as applied to the valve and plate,

with a modification in the arrangement of the balancing devices; Fig. 4, a plan view of the same with one half on the steam-chest cover maintaining the true parallelism of the balancing-plate with the valve-scat when the supporting constructions are secured in a fixed form a ball-andsockct connection therewith.

To this end I make the aperture through the valve-chest cover G sufficiently large to permit any required angular adjustment of the rod D, and countersink said aperture at the outside of the cover to receive a stuffing-box, H, having a semi-spherical bottom, forming a ground steam-joint with the cover G. The stuffing'box His provided with an ordinary gland, a, secured by bolts in the usual manner, and is extended laterally into a circular flange or disk, h, provided at suitable intervals with holes, somewhat enlarged for the passage of retaining-bolts b, by which'it is sccurely bolted to the steam-chest cover when adjusted. By means of this construction, in case the valveseat should become worn out'of its true horizontal plane or'the valve-chest cover lose its proper alignment through irregularities of the packing, and the rod D be ,thrown out of its true perpendicular relation to said cover, it may nevertheless be secured in its proper position and the stufling-box be adjusted in proper relations thereto by means of its spherical joint and its retaining-bolts, as will be readily understood.

As a means ofseating the plate to its proper position on the back of the valve,and thereby obtaining the proper adjustment of the rod D in the steam-chest cover, I employ four bolts, 0, threaded through the steam chest cover above and bearing against the top of the plate 0 near its four corners. These are to be used only in seating the plate temporarily to obtain the specified adjustments. When so obtained and the stuffing-box H secured in its seat, the bolts 0 are to be loosened sufficiently to allow the plate to be under control of its balancing springs and piston, as hereinafter described.

In the present case I have shown (in Figs. 1 and 2) the balancing mechanism of "the plate 0 asa steam cylinder and piston, and a double ICO spring, S, connected by anintermediate lever, E, with the rod D. The rod D passes through an enlarged perforation at one end of the lever, and is secured by a nut,f, having'a hemispherical base seated in a correspondinglycountersunk washer, w, a connection permit-- chest with the cylinder]? above its piston I.

The piston-r0d gis extended also downward beyond the cylinder F and through two leaf or plate springs, S S, upon standards i i at their ends. The springs consist of two concaved sections or plates, (as more fully exhibited in the modified arrangement, Fig. 3,) with convexities outward, and secured horizontally between and upon standards i i,depending from bottom of the cylinder forming the end extension ofthe valve-chest cover. The holes by which the springs are secured upon their standards may be enlarged to permit longitudinal adjustment to accommodate the other parts. The connecting-rod g is rendered'vertically adjustable in relation to the springs by set-nuts n, threaded upon the rod above and below against the springs,by which means the exact balance of the plate may be secured. The fulcrum of the lever E is rendered adjustable by the following construction: The fulcrum proper isa flanged friction-roller, 7c, j ournaled in a jaw-piece, I, mounted on a plate, m, secured by corner-posts to the steam chest cover. Thestem'jaw-piecel projects through a slot, 0, in the plate at and is secured by set nuts, by which the position of the fulcrum in relation to the lever can be adjusted as de- "sired and the relative length of the leverand in the vertical line of said valves below,

in the lower head of the cylinder, corresponding set-screws, 0, forming abutments against which the stem of the valve strikes in case the piston descends below its normal limit. I also provide an opening in the lower head, so that in case the piston extends below its normal limit, as sometimes occurs through overpress- 1 ure of steam or water in the cylinder F, the striking of the valve-stems against the setscrews lifts the valves and allows the steam or water to escape. In the same connection I have shown apertures 16 in the back of the main valve A, (indicated by dotted lines in Fig. 1 and in plan in Fig. 2,) by which, in case the plate 0 is lifted by any overpressure from the back of the valve, the pressure may be relieved and the steam or water in the valvechest escape through the exhaust-port. These two relief devices may be employed either singly or both together.

In the space between the apertures tthe back of the valve may be recessed, as described in my said former application, or the plate 0 may contain such recess. The same forms the oil and vacuum chamber communieating with the aperture of the hollow rod D.

In Fig. 3 I have shown a slightly-modified arrangement of the balancing cylinder and springs, in which a lever is dispensed with and the balancing cylinder and springs are both in the vertical axis of the balancing-plate. The employment of the balancing springs and p ston together, in combination, is much preferred, and, so far aslam aware, is novel. The function of the same in combination is as follows: In the use of a steam-engine, particularly in locomotives, the valve is in operation at times without steam. At such times, were the plate supported only by a balancing-p1ston, its weight would be added to that of the valve and increase the wear upon the valve-seat. On the other hand, when under steam, were the balancing-springs alone used and ad usted to the weight of the valve, the excessive pressure upon the plate would be added to the weight of the valve, and thereby increase the wear upon the valve-seat.

By using the springs and balancingpiston .object being to resist movement in both directions. The connection of the rod D by its setnuts n n above and below the springs allpws the springs to act independently as against site directions, yet by the relative adjustment "of the nuts the springs may be brought into tension, each to modify the force of the other. The springs thus not only assist in overcoming the downward pressure of steam upon the plate, but also resist the upward pressure of steam beneath the valve, thus maintaining the parts in a more nearly perfect balance or equilibriunlat all times.

The plate 0 may be formed with depending side flanges, K, forming a tongue-andgroove connection with the valve, as shown in Fig. '6. I may also employ in connection with the hollow rod, plate, and valve, constructed as described, a spring-seated check-valve, Z, opening downward in an opening through the back of the valve centrally into the exhaust-chamher, and a similarly-arranged check-valve, m,

I r 5 vertical movements of the pistonrod in oppoat the top of the hollow rod D, governing the opening through the rod. The object of the valves is to prevent the escape of steam or oil upward through the hollow rod in case of leak age of steam between the valve and plate into the vaouum-ehamber.

I claim as myinvention and desire to secure by Letters Patent of the United States- 1. In a balanced valve, the combination of the balancingplate and its supporting-rod with the adjustable stuffing-box in the steam chest cover, substantially as set forth.

2. In a balanced valve, in combination with the balancing-plate, its supporting-rod, the steam-chest cover, and the adjustable stuffingbox, the bolts threaded in the steam-chest cover and adjustable against the back of the plate, substantially as set forth.

8. The combination, in a balanced valve, of the valve having a plane back parallel with its face, a relief-plate provided with dependi ng side flanges, forming a horizontal slot-andfeather engagement with the valve, and means, substantially as described, for balancing the plate against pressure in both directions, sub- 25 stantially as set forth.

4. In a balanced valve, in combination with the relief'plate, a valve provided with apertures t, opening into the exhaust-cavity, substantially as and for the purpose set forth.

5. In a balanced valve, in combination with the balance-plate and its supporting-r0d, the springs S, composed of two members acting in opposite directions to resist pressure of steam upon the plate and to relieve the weight of the 3 5 plate when steam is shut off, substantially as set forth. 7,

'6. In a balanced valve, the steam balancingpiston provided with one or more check-valves, in combination with adjustable screws 0, ar- 0 ranged and operated as set forth.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

WILLIAM W. LEWIS. WVitnesses:

L. M. HosEA,

O. D. KERR.

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