US747109A - Corliss valve-gear for steam-engines. - Google Patents

Description

No. 747,109. PATENTED DEC. 15, 1903.

W. WRIGHT, DECD.

M. E. WEIGHT, ADMINISTRATRIX. OORLISS VALVE GEAR FOR STEAM ENGINES. APPLICATION FILED AUG. 9, 1902. RENEWED NOV. 13. 1903.

N0 MODEL. 3 SHEETS-SHEET 1.

No. 747,109. PATENTED DEC. 15, 1903.

W. WRIGHT, DEGD M. E. WRIGHT, ADMINISTRATBIX. GORLISS'VALVE GEAR FOR STEAM ENGINES. APPLICATION FILED AUG. 9, 1902. RENEWED NOV. 13, 1903 N0 MODEL. 3 SHEETS-SHEET 2.

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M. E. WR I TRATRIX. OORLISS VALVE G AR FOR STEAM ENGINES. APPLICATION FILED AU .9, 1902. RENEWED NOV. 13, 1903.

W IGHT' G'D. 1G T ADMIN S UNITED STATES Patented December 15, 1903.

. PATENT UFHCET WILLIAM WRIGHT, or RRooKLYN, NEW YORK; MARY E. WRIGHT ADMIN- ISTRATRIX or SAID WILLIAM WRIGHT, DECEASED.

CORLISS VALVE-GEAR FUR STEAM-ENGINES.

SPECIFICATION forming part of Letters Patent 0. 747,109, dated December 1 1903- Application filed August 9, 1902. Renewed November 13, 1903- Serial No. 181,097. (No model.)

T0 on whom it may concern:

Be it known that I, WILLIAM WRIGHT, a citizen of theUnited States, residingin Brooklyn, in the county of Kings and State of New York, have invented certain new and useful Improvements in Corliss Valve Gears for Steam-Engines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in valve-gears for steam-engines, and particularly to improvements in valve-gears of the (Jorliss type.

My invention resides in the novel tripping devices employed and in the novel combination, construction, and arrangement of the parts.

The object of my invention is to improve and simplify Corliss valve-gears. This ob ject is attained in the invention herein described, and illustrated in the drawings which accompany and form a part of this specification, in which the same reference-numerals indicate the same or corrresponding parts, and in which- 7 Figure 1 is a side elevation of a horizontal steam-engine provided with my va1ve-gear. Fig. 2 is a larger detail elevation of the en'- gine-cylinder, wrist-plates, and connected parts of the valvegear, the ends of thecylinder and the steam and exhaust valves being sectioned. Fig. 3 is a vertical cross-section of the engine-cylinder and valve-gear through the center of the primary wrist-plate. Fig. dis a detail view showing a portion of the primary wrist-plate with one of the segmental secondary wrist-plates thereon, the latter being sectioned to show the trippingrod which passes through it; and Fig. 5 is a detail side elevation of the tripping-bar.

In the drawings, 1 designates the enginecylinder; 2, its steam-chest; 3, its exhaustreceiver; 4, the crank-shaft; 5, the valve-operating eccentric thereon, and 6 the eccentric-strap. The eccentric-rod is formed for convenience in two sections 7 and 7", connected by a rocking lever 8.

The wrist-plate 9, termed a primary wrist-plate to distinguish it from secondary wrist-plates hereinafter mentioned mounted adjacent to it, is mounted, as customary, upon a stud 10, projecting from the enginecylinder. This stud is hollow and contains a tripping-bar 11, to which reference will be made hereinafter. The eccentric-rod 7" is connected to the wrist-plate 9 by means of a stud 12, projecting therefrom.

Steam-valves 13 and 14 are located at opposit-e ends of the engine-cylinder Within valve-chambers which communicate with the interior of the engine-cylinder through ports 15 and 16 and which also communicate with the steam-chest 2. Exhaust-valves 17 and 18 are located within valve-chambers which communicate with the interior of the enginecylinder by means of ports 19 and 20, respectively, and which also communicate with the exhaust-receiver 3. The valves are provided with crank-arms 21, 22, 23, and 24, respectively, by which they may be rotated within their valve'chambers. The cranks 21 and 22 of the steam-valves 13 .and 14 are connected by rods 25 and 26 to studs projecting from two valveoperating segmental secondary wrist- plates 27 and 28, respectively, revolubly mounted upon the same stud 10 which carries the primary wrist-plate 9 and located adjacent to said primary wristplate. These segmental wrist-plates or segments are not directly secured to the primary wrist-plate 9, but are provided with cheeks 29 and 30, respectively, with which springpressed pawls 31 and 32, pivoted to the wristplate9, may engage. Beneath these checks the edges ofthe segments are recessed slightly, so as to limit the inward movement of the .pawls. Within each segment is a radial bore, within which is a tripping-rod One end 9c of each of these tripping-rods is opposite the corresponding pawl 31 or 32 when the latter is in engagement with the corresponding cheek of the segment, the other end of the said rod lying within one of two grooves 34 in the trip- 5 ping-bar 11. The Stud 10, within which said tripping-bar is mounted, is provided with slots 35, opposite and corresponding to these grooves 34, through which the tripping-rods may pass, and the hub of each segment is [CO quick acting in its operation.

provided with a corresponding slot to permit the passage of the tripping-rod of the other segment. Each tripping-rod is pressed inwardly by a spiral spring 36, located Within the corresponding segment.

To the segments 27 and 28 are connected rods 37 and 38, respectively, leading to the pistons of vacuum-pots or equivalent valve-' closers 39 and 40, respectively. These vacuum-pots or valve-closers may be of ordinary construction.

The cranks 23 and 24 of the exhaust-valves l7 and 18 are connected directlyto the wristplate by means of rods 41 and 42 and corresponding studs projecting from the wristplate.

43 is a centrifugal governor of ordinary construction. It should be ofa type which is very This governor may be driven in any convenient manner. I have shown a belt-wheel 44, which may be driven by a belt itself driven from the cran kshaft of the engine in the ordinary manner for this purpose. The beltis not shown. The stem 45 of the governor is connected by a crank-arm 46, Fig. 3, to a rock-shaft 47. This rock-shaft extends to a point opposite the trippingbar 11 and is there provided with a crank 48, Fig. 3. To the tripping-bar is connected a pivoted rocking lever 49, and said lever is connected to the crank 48 by a rod 50. The connections between the governor and tripping-bar are such that as the speed of the engine rises and the governor-balls fly outward the tripping-baris moved inward. That edge of the groove 34 in the tripping-bar 11 which is uppermost in Fig. 5 is beveled, as shown in said figure and also in Fig. 4. The same is true of the corresponding edge of the groove upon the other side of the tripping-bar. When the segment 27, for instance, moves upward, its tripping-rod 33 at some point in said upward movement encounters the upper beveled edge of the groove 34 and is moved outward against the pressure of its spring 36, moving upward the pawl 31, and so releasing the segment, which is then drawn downward by the vacuum-pot 39. The point in the engine-stroke at which this release of the segment and the consequent closure of the valve takes place is determined by'the position of the tripping-bar. When the engine is first started in motion and the speed of the engine is slow, the tripping-bar is in its outermost position, and the end of the tripping-rod 33 works back and forth in the right-hand side of the groove 34,as said grooveisseen in Fig.5. As the speed of the engine rises, the tripping-bar is moved inward, and if the speed rises above the normal the tripping-bar is moved so far inward that the rod encountersthe inclined edge of the groove 34 at some time prior to the time when the eccentric reaches its deadcenter, and so trips its valve. The governor adjusts the position of the trippingbar, so as to cause the engine to cut off at the point in its stroke which insures the maintenance of uniform speed. If the speed falls, the governor moves the tripping-bar outward, so lengthening the period of admission and causing the engine to cut off later in the stroke. The width of the groove 34 at its narrower end is such that the valve is released almost instantly after it begins to open.

What has been said above of the unlatching of the segment 27 is also true of the unlatching of the segment 28.

The upper beveled edges of the grooves 34 may be termed cam-shoulders, since they form, inetfect, the working faces of cams which force the rods outward when they encounter said rods.

The steam-valves,consist,essentiallyof hollow cylinders 52, having central perforated partitions 53, which at the base are broadened and provided with outer recesses 54.

Upon each side of the broadened base of the partition'53 are steam-ports numbered and 56, respectively. There is also another port, 57, in each valve communicating with the steam-chest 2. In the side of the valvechamber of each valve is a recess 58. Steam is admitted from the steam-chest into the interior of each valve through the ports 57. When one of the valves is open, steam passes from its interior through its port 55 into the cylinder-port 15 or 16 and also through the port 56, recess 58, and the recess 54 of the valve into said cylinder-port. A very slight movement of the valve thus suffices to afford large port-opening at the beginning of the stroke, and wire-drawing is thus avoided.

As the steam-valves of Corliss engines have usually been constructed heretofore difficulty has been experienced from wear of the valves and valve-seats due to unbalanced pressure of steam forcing the valve downward upon its valve-seat and sometimes flexing the valve slightly, thus causingit to wear off the edges of its ports and of the ports in its seat; but in this valve the pressure of steam acts with substantial uniformity in all directions. Moreover, since the valve completely fills the valve-chamber and has a bearing throughout its circumference excessive pressure at anyone point is avoided, while the tubular section of the valve renders it so stifi that it does not bend.

The exhaust-valves are also double-ported. Each valve consists of acylinder 59, provided with an internal port and also with a recess 61, which also forms, in effect, a port. When the valve is open, in which position valve 18 is shown in Fig. 2, steam passes from the engine-cylinder through the passage 60 and also through the recess 61 into the exhaust-receiver 3.

The operation of my valve-gear is as follows: In the drawings the parts of the engine are'shown in the positions assumed during the first part of a forward stroke of the engine, the steam-valve 13 at the rear end of the engine-cylinder and the exhaust-valve 18 at the front end of the cylinder being open. The eccentric is near its front center and the upper side of the wrist-plate is moving forward. The pawl 31, corresponding to segment 27, is in engagement with the cheek 29 of said segment, so that said segment is being lifted. Live steam is entering the rear end of the engine-cylinder through ports 55 and 56 of the valve 13 and exhaust-steam is passing from the front end of the engine-cylinder through ports 60 and 61 of the valve 18. The tripping-rod 33 of the segment 27 has not encountered as yet the cam edge of the groove in the tripping-bar 11. When said rod does encounter said edge, the pawl 31 is pressed outward, and so out of engagement with the cheek 29. The vacuunrnpot 39 immediately draws downward the segment 27, closing the steam-valve 13 and cutting off steam. While the primary wristplate 9 has been moving forward the pawl 32, corresponding to wristplate 28, has moved below the cheek 30. It over-travels somewhat; but during the backward movement of the wrist-plate and some what before the back stroke of the engine begins the pawl 32 encounters said check 30 and lifts the segment 28, so as to take up the lap of the valve 14 and open said valve at the beginning of the back stroke. The pawl 32 is tripped in the same manner as pawl 31 by the corresponding cam-shoulder of the tripping-bar 11 at the proper point in the stroke, so that segment 28 falls and closes valve 14. The governor by adjusting the position of the tripping-bar 11 regulates the point at which cut-off takes place in each end of the engine-cylinder. If the speed of the engine be too high, the governor moves the trippingbar inward, so that the shoulders of the grooves 34 engage the rods 33 and trip the valves earlier in the stroke. If, on the other hand, the speed of the engine be too low, the governor moves the tripping-bar outward, so that the valves are released later in the stroke.

The exhaust-valves are opened and closed by the wrist-plate 9 in the ordinary manner.

Having thus completely described my invention, what I claim, and desire to secure by Letters Patent, is-

1. In a valve-gear, the combination, with a valve, a primary valveactuating device, means for vibrating the same, a secondary valveactuating device, connected to said valve, and a latch adapted to connect said primary and secondary valve-actuating devices, of a tripper, a tripping-rod vibrating with one of said valve-actuating devices and coacting with said tripper, and adapted when operated to operate the latch and release said secondary valve-actuating device, and means for closing the valve when said secondary valve-actuating device is released.

2. In a valve-gear, the combination, with a valve, a primary valve-actuating device, revolubly mounted, means for vibrating the same, a secondary valveactuating device likewise revolnbly mounted, and connected to said valve, and a latch adapted to connect said primary and secondary valve-actuating devices, of a tripper, a radial [ripping-rod vibrating with one of said valve-actuating devices and coasting with said tripper, and adapted when operated to operate the latch and release said secondary valve-actuating 4. In an engine, the combination, with an engine-cylinder having admission-valves at its ends, a primary wrist-plate, means for vibrating the same, two secondary wrist-p1ates connected each to one of said valves, and latches adapted to connect said primary and secondary wrist-plates, of a tripper, a separate tripping-rod for each of said secondary wrist-plates, carried thereby and coacting with said trippeig'and adapted when operated to trip the latch of said secondary wristplate, and means for closing each valve when the corresponding secondary wrist-plate is released. l

5. In a valve-gear, the combination, with a valve, a primary valve-actuating device, revolubly mounted,means forvibrating the same, a secondary valve-actuating device likewise revolubly mounted, and connected to said valve,and a latch adapted to connect said primary and secondary valve-actuating devices, ofa tripper movable laterally with respect to said valve-actuating devices, and having an inclined cam shoulder, means, carried byone of said valve-actuating devices, and operated by contact with said cam-shoulder, for tripping the latch and releasing said secondary valve-actuating device,and means for closing the valve when said secondary valve-actuating device is released.

6. In a valve-gear, the combination, with a valve, a primary valve-actuating device, revolubly mounted, means for vibrating the same, a secondary valve-actnating device connected to said valve, and mounted to rotate about the same axis of rotation as the primary valve-actuating device, and a latch adapted to connect said primary and secondary valve-actuating devices, of a trippingbar located at the center of rotation of said valve-actuating devices, and movable later ally, with respect to said valve-actuating devices, and having an inclinedcam-shoulder, means, carried by one of said valve-actuating devices and operated by contact with said cam-shoulder, for tripping the latch and releasing said secondary valve-actuating device, and means for closing the valve when said secondary valve-actuating device is released.

- 7. In a valve-gear, the combination, with a valve, primary and secondary wrist-plates, revolubly mounted upon a hollow stud, the secondary wrist-plate being connected to said valve, means for vibrating the primary wristplate, and a latch adapted to connect said primary and secondary wrist-plates, ofa tripping-bar mounted within said stud, and movable longitudinally therein, and having an inclined cam-shoulder, a tripping-rod vibrating with one of said wrist-plates, and adapted to be pressed outward by said cam-shoulder and thereby to trip the latch, thereby releasing said secondary wrist-plate, and means for closing the valve when said secondary wrist-plate is released.

8. In an engine, the combination, with an enginecylinder having admission-valves at its ends, a primary wrist-plate, and two secondary wrist-plates, revolnbly mounted upon a hollow stud, said secondary wrist-plates being connected each to one of the said valves, means for vibrating the primary wrist-plates and latches adapted to connect said primary and secondary wrist-plates, of a tripping-bar mounted within said stud and movable longitudinally therein, and having two inclined cam-shoulders, two tripping-rods vibrating with said wrist-plates, and adapted each to be pressed outward by one of the cam-shoulders and thereby to trip one of said latches, and means for closing each valve when the corresponding secondary wristplate is released.

9. In a valve-gear, the combination, with a hollow stud, a primary wrist-plate mounted thereon, two secondary wrist-plates, likewise mounted thereon and adjacent to said primary wrist-plate, and latches adapted to connect said primary and secondary wrist-plates, of a tripping-bar mounted within said stud and movable longitudinally therein, tripping devices adapted to be operated by said tripping-bar, for tripping said latches, and means for moving the tripping-bar.

10. In a valve-gear, the combination, with primary and secondary wrist-plates, revolubly mounted, of a pawl carried by one of said wrist-plates and adapted to engage a shoulder on the other of said wrist-plates, and a tripping device carried by one of said wristplates by which said pawl may be tripped.

ll. In a valve-gear, the combination, with primary and secondary wrist-plates, mounted to revolve about the same axis of rotation, and meansfor vibrating one of said wristplates, of a pawl carried by one of said wristplates and adapted to engage a shoulder on the other of said wrist-plates, and a trippingrod lying within a radial bearing in one of said wrist-plates and engaging a tripping-bar located at the axis of revolution of the wristplates, said tripping-rod being adapted to trip said pawl when operated.

In testimony whereof I affix my signature in the presence of twowitnesses.

WM. WRIGHT. Witnesses:

CHARLES LA 0. HOFF, HARRY M. MARBLE.

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