US678807A

US678807A - Compound engine.

Info

Publication number: US678807A
Application number: US4341499A
Authority: US
Inventors: Marcy L Whitfield
Original assignee: WHITFIELD Co
Current assignee: WHITFIELD Co
Priority date: 1899-07-05
Filing date: 1899-07-05
Publication date: 1901-07-16
Anticipated expiration: 1918-07-16

Description

(No Model.)

Patented July l6, I90l. M. L. WHETFIELD.

COMPOUND ENGINE.

(Apphcation filed July 6,1899. Renewed Jan. 15, 1901.)

4 Shoats-Shaet l.

m5. 6.2mm. Patented July l6, mm. m. L., mmnun.

CUMPUHNB ENGINE.

(A. L'cation filerl 5 1889. Banewed. Jan. 15, 1901.) am new, pp I 4 Sheets-Sheet 2.

T: NORRIS PETERS co. vncwmno. WASHINGTON, a c.

. m m .W u I d e t n a t a P R L E F H H W L M COMPOUND ENGINE.

(Application filed July 5, 1899. Renewed Jan. 15, 1901.)

4 Sheets-Sheet 3.

(No Model.)

Patented luly l6, I90l.

Mr L. WHITFIELD. COMPOUND ENGINE.

(Application filed July 5, 1899. Renewed Jan. 16, 1901.)

4 Sheot-Sheet 4.

' (No Model.)

Unitar an Marne nrnnr FFlQE.

MARGY L. VVIIITFIELD, OF MEMPHIS, TENNESSEE, ASSIGNOR TO THE WVIIITFIELD COMPANY, OF SAME PLACE.

COMPOUND ENGINE.

filEGIFIGATXON forming part of Letters Patent No. 678307, dated July 16, 1901.

Application filed July 5,1899, Renewed January 15, 1901. Serial No. 43,414. (No model.)

T 0 ctZZ whom, it may concern:

Be it known that I, MARCY L. WHITFIELD, a citizen of the United States of America, residing at Memphis, in the county of Shelby and State of Tennessee, have invented certain new and useful Improvements in Compound Engines; and I do hereby declare the following to be afull, 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, reference being had to the accompanying drawings, and to letters and figures of reference marked thereon, which form a part of this specification. i

This invention has relation to compound telescopic steam-engines, and more particularly to that type in which the high-pressure cylinderworks on a stationary piston or abutment and performs the function of piston for the low-pressure cylinder.

The invention has for one object a construction of vertical engine wherein all stuff ing-boxes are dispensed with and the waste of steam from leakage at the stuffing-boxes and the expense, labor, and attention to the packing thereof are avoided.

A further object of the invention lies in the provision of means whereby under certain conditions of work the engine is automatically caused to work simple for the purpose of utilizing under such conditions the great reserve power common to this type of engines.

A further object of my invention lies in the construction and cooperation of the main, intermediate, and exhaust valves and in the provision of means for balancing the intermediate valve in such a manner as to avoid its being held to its seatby back pressure in the low-pressure cylinder.

That my invention may be fully understood I will describe the same in detail, reference being had to the accompanying drawings, in which- Figure 1 is an elevation of a vertical compound steam-engine embodying my invention. Fig. 2 is a perspective sectional view taken on line A B of Fig. 4. Fig. 3 is a vertical section taken on line C D of said Fig. 4. Fig. 4 is a top plan View of the engine. Fig. 5 is a section onlineE F of Fig. 2. Figs.

6 and 7 show the main valve by a perspective view and a cross-section, respectively; and Figs. 8, 9, 10, and 11 show the intermediate valve by a perspective View, a crosssection, a vertical sectional view, and an under side view, respectively.

As shown in Figs. 1, 2, and 3, the body of the engine is built up of sections a b c, of which a constitutes the base, and c the lowpressure cylinder, said sections being bolted together in any well-known manner. The section a has bearings for the power-shaft composed of two stub-shafts d d, on the proximate ends of which are mounted crank-disks e e. Each of the stub-shafts d d carries a fly-Wheel Zat its outer end, and one of said shafts carries an eccentricm, controlled by a centrifugal governor n of well-known construction.

To the intermediate section Z) is secured a fixed abutment f, extending axially upward and to a suitable extent into the low-pressure cylinder 0, said abutment being properly packed and constitutes the piston for the high-pressure cylinder g.

In the base h of the piston-abutment f is formed a passage 2', to which the steam-supply pipe 70, leading to the boiler, is connected.

The high-pressure cylinder g has at dia metrically opposite points wrist-pins 0 for one end of connecting-rods p, the other ends of which are secured to an equalizing-bar q, pivotally connected to a crank-rod r, mounted on the crank-pin of the crank-disks e on powershaft d.

In order to admit of the adjustment of the connecting-rods p relatively to the crank-pin on the crank-disks e, the lower end of said rods is screw-threaded and is screwed into correspondinglythreaded bearings in the equalizing-bar q, the adjustment being effected by means of suitable nuts 30, Fig. 2.

In the stationary piston-abutment f is formed a valve-chamber for the main valve 8, and in the heads of the high and low pressure cylinders g c are formed valve-chambers for the intermediate valve t and the exhaustvalve M, respectively, and o is the exhaustpipe leading from an exhaust-passage 21 in the casing ofthe exhaust-valve.

The main or distributing valve 3, the intermediate valve '6, and the exhaust-valve u are all oscillating cylindrical valves. The intermediate valve has a stem 10 polygonal in cross-section and is fitted to slide in a corresponding bore in the exhaust-valve M, which latter is connected by a link a; to a radial arm on a valve-operating rod 2 and to a radial arm y on a collar secured to the outer attenuated end of the exhaust-valve u. The main or distributing valve 8 is likewise operated from the rod z, a radial arm 25 thereon being connected through a link ,3 with a radial arm 2 on the stem 24: of said valve 8, Figs. 2, 4, and 5.

The rod .2, which oscillates in suitable bearings formed in brackets 4, bolted to the end flanges of the low-pressure cylinder 0, has a radial arm 26, connected by a link 5 to one arm of a bell-crank lever 6, fulcrumed on a stud or pin secured to the engine-section b,

the other arm of said bell-crank lever being connected through rod 7 with the valve controlling eccentric m on power-shaft d in the usual manner.

The open lower end of the valve-chamber in the fixed piston-abutmentfis closed by a flanged plug 8, having a bore through which extends the stem 24 of the main valve 3, so that ready access is had to said chamber and valve, and said plug 8 has drainage-passages formed therein for the eduction' of water of condensation. main valve 8 is formed a circular steam-passage 9 and vertical passages 10 and 11, which latter merge into an axial passage 12, formed in the upper portion of the stationary pistonabutmentf.

The main valve 8 has a recess or cavity 13 in its upper end and a similar cavity'lt in its lower end, Figs. 2, 3, and 6, said cavities or chambers being connected by a passage 15, Fig. 2. The said main valve has longitudinal main ports 28 and similar but narrower subsidiary ports 29, through which the passages 10 and 11 in the chamber for said valve are placed in communication.

In the valve-chamber formed in the head of the high-pressure pistoncylinder g are formed passages 16, and the cylindrical intermediate valve 6 has a circular chamber 29 Figs. 8 and 9, in its upper end in communication with the peripheral ports 17, and in its under side said valve t has a cavity 18, Figs. 10 and 11, in communication with chamber 29 through passages 19. p

In the head of the low-pressure piston-cylinder are formed passages 22, leading into the valve-casing 27, preferably formed on said head, said passages 22 adapted to be placed in communication with a circular passage 21, connected with the exhaust-pipe 0 through passages 23*, formed in the exhaust-valve M,

Fig. 2.

In engines of the type under consideration it is of great importance that the intermediate valve 15 should be perfectly balanced, and as it is desirable that this valve should also Around the chamber for the be as large as possible, so that its ports when open will displace as much of the back-pressure area of the high-pressure-piston-cylinder head as possible it will be seen that although the valve may be balanced it will still have a very great seating-pressure under the action on said valve of the steam in the lowpressure cylinder. This I avoid by chambering the under face of the valve and connecting the chamber 18, through passages 19, with the circular open chamber 29 of said valve, as hereinabove described, so that any pressure in the low-pressure cylinder 0 will be exerted equally on both valve-faces, thus preventing excessive seating-pressures and effectually preventing the valve from sticking. Similar provisions are made for the main valve 3 through the

chambers

13 and 14 and their communicating passage 15.

The operation of the described engine is as follows: Assuming the high-pressure pistoncylinder to be in the position shown in Fig. 2, for instance, or at or about at the limit of its downstroke and when the main valve sis in a position to establish communication between the passages 10 and 11, through the longitudinal ports 28 of said valve 8, the throttle-valve beingopen, live steam flows through pipe and passage t' into circular passage 9, and thence through passage 10, valve-ports 28, passages 11 and 12 into the high-pressure piston cylinder, the intermediate and ,exhaust valves 25 and to closing the steam-passages controlled thereby. The high-pressure piston-cylinder g makes its instroke, and as it is about to reach the limit of its said stroke the intermediate valve is oscillated to bring its ports 17 into register with the passages 16, thus allowing the live steam to exhaust from said cylinder into the low-pressure cylinder 0, causing the former to make its outstroke, during which movement the intermediate valve 25 is oscillated in a reverse direction to cut off the communication between the said two cylinders. As the high-pressure piston-cylinder reaches the limit of its outstroke the exhaust-valve is oscillated to establish communication between the exhaustpassages 21 and 22 through the ports 23 in said exhaust-valve a. At or about the same time the main valve 8 is oscillated to again admit steam to the high-pressure piston-cylinder g, as above described, and as the latter is about to reach the limit of its instroke the exhaust-valve u is oscillated in a reverse ditionso that after live steam has been ad mitted into the high-pressure piston-cylinder 9 through the ports 28 of valve 5, and as the said cylinder moves inwardly the ports 29 of said valve 5 will be brought into position to establish communication between the passages 10 and 11 at a time when the intermediate valve t has established communication between the high and low pressure cylinders, so that live steam is admitted directly into the low-pressure cylinder 0 to cause the highpressure pistoncylinder g to make its outstroke, the exhaust-valve it being closed. As the high-pressure piston-cylinder reaches the limit of its said outstroke the exhaust-valve establishes communication between the lowpressure cylinder 0 and the exhaust-passage 21. At the same time the intermediate valve closes and live steam is admitted to the highpressure piston-cylinder g, first I through the ports 28 of valve 3 to effect the instroke and as said cylinder is about to reach the limit of its instroke, at which moment the intermediate valve if has established communication between the high and lowpressure cylinders, live steam is admitted to said high-pressure cylinder through the ports 29 in the main valve, and consequently to the low-pressure cylinder, to effect the outstroke, which operations are repeated, the engine working simple; but as the speed of the engine increases the centrifugal governor 'n will draw the center of the eccentric m, that controls the valves 8 if to, closer to the center of the power-shaft d, and when the engine is working at a normal speed the amplitude of the oscillations of the main valve 8 will be sufliciently reduced to prevent the ports 29 in said valve from establishin g communication between the passages 10 and 11, so that as the intermediate valve 25 establishes communication between the high and low pressure cylinders no live steam from the supply-pipe 7r will be admitted to the highpressure cylinder, while the live steam in the latter will pass into the low-pressure cylinder and effect the outstroke by expansion, as hereinabove set forth, the engine working compound.

From what has been said it will readily be seen that should the normal speed of the engine be reduced from any causeas, for instance, by an increase of a load thereon-the travel of the main valve will be correspondingly increased and the engine caused to work as a simple engineto overcome the in creased load, and as soon as the speed of the engine has again become normal the operation of the said main valve will also become normal and cause ,the engine to operate as a compound engine.

Having thus described my invention, What I claim as new therein, and desire to secure by Letters Patent, is-

1. In a compound telescopic vertical steam= engine, the combination with a low-pressure cylinder, a stationary piston-abutment, and

a high-pressure piston-cylinder working on said abutment and in said low-pressure cylinder, an oscillating cylindrical main valve arranged in said abutment, a similar intermediate valve arranged in the head of the high-pressure piston-cylinder, a like exhaustvalve arranged in the head of the low-pressure cylinder, means for transmitting the movements of the exhaust-valve to the intermediate valve, suitable steam-passages controlled by said valves, and means for operating the main and exhaust valve from the power-shaft of the engine, for the purpose set forth.

2. In a compound telescopic vertical engine, the combination with a low-pressure cylinder, a stationary piston-abutment and a high pressure piston cylinder working on said abutment and in said low-pressure cylinder, of cylindrical oscillating controllingvalves mounted on the abutment, and in the head of the high-pressure cylinder respectively, and a valve-gear, said valves and valve gear constructed and operating to cause the engine under normal conditions to work as a compound engine, and as a semicompound engine in starting or under an increase of the load, for the purpose set forth.

3. In a compound telescopic vertical steamengine, the combination with a low-pressure cylinder, a stationary piston-abutment, and a high-pressure piston-cylinder working on said abutment and in said low-pressure cylinder; of cylindrical oscillating valves arranged in said abutment and in the head of said high-pressure piston-cylinder, respectively, said valves constructed and operating to permit live steam to flow into the highpressure piston-cylinder and to then expand into the low-pressure cylinder, and means for equalizing the steam-pressure on opposite ends of the valve in the head of the highpressure piston-cylinder, for the purpose set forth.

4. In a telescopic vertical compound steamengine, the combination with a low-pressure cylinder, a stationary piston-abutment, and a high-pressure pistoircylinder working on said abutment and in said low-pressure cylinder; of cylindrical oscillating valves arranged in said abutment and in the head of said high-pressure piston-cylinder, respec' tively, said valves constructed and operating to permit live steam to flow into the highpressure piston-cylinder and to then expand into the low-pressure cylinder, and means for equalizing the steam-pressure on opposite ends of the valve in the aforesaid abutment, for the purpose set forth.

5. In a telescopic vertical compound steamengine, the combination with a low-pressure cylinder, a stationary piston-abutment, a high-pressure piston-cylinder working on said abutment and in said low-pressure cylinder, and the power-shaft; of an equalizing-bar, a connection between said bar and the crank bar and with the crank of the power-shaft,

and connecting-rods adj ustably connected with the equalizing-bar and connecting the latter with the high-pressure piston-cylinder, for the purpose set forth.

7. The combinationwith the high-pressure piston-cylinder 9 having wrist-pins 0 at diametrically opposite points,the two-part powershaft d d having disks at the proximate ends of its parts, the equalizing-bar q, the connecting-rod r pivotally connected with said bar and with the crank of the crank-shaft, and connecting-rods p connected With the aforesaid wrist-pins 0 and equalizing-bar q, substantially as and for the purpose set forth.

8. In a compound telescopic vertical steamengine, the combination with a low-pressure cylinder, a stationary piston abutment, a high-pressure cylinder working on said abutment and in said low-pressure cylinder, cylindrical oscillating valves arranged respectively in the stationary abutment and the heads of the high-pressu re cylinders, the valve in the stationary abutment provided with two sets of distributing-ports, and suitable steampassages controlled by said valves; of the power-shaft, an eccentric thereon, a governor controlling said eccentric, and means for transmitting the necessary oscillating movements to the aforesaid valves through said eccentric, substantially as and for the purpose set forth.

9. In an engine of the type described, a high-pressure piston-cylinder, provided near its piston head at diametrically opposite points with Wrist-pins cast thereon for the connecting-rods through which said cylinder is connected with the power-shaft of the engine, as set forth.

10. In a telescopic vertical compound steamengine comprising a low-pressure cylinder, a stationary piston-abutment, a high-pressure piston-cylinder working on said abutment and in said low-pressure cylinder, and driving-rods connected with the high-pressure piston-cylinder at points outside of the steam.

area confined by the packing; of oscillating self-packing main, intermediate and exhaust valves, located in chambers 0n the stationary piston-abutment, and in the heads of the high and low pressure cylinders respectively, means located wholly within the steam area of the low-pressure cylinder, for operating the intermediate valve from the exhaust-valve, and means located outside of the steam areas of the main and exhaust valves for operating the same, for the purpose set forth.

11. In a telescopic vertical compound steamengine comprising a low-pressure cylinder, a stationary piston-abutment, a high-pressure piston-cylinderworking on said abutment and in said low-pressure cylinder, and drivingrods connected with the high-pressure pistoncylinder at points outside of the steam area confined by the packing; of oscillating selfpacking main, intermediate and exhaust valves located in chambers in the stationary piston-abutment, and in the heads of the high and low pressure cylinders, respectively, means located wholly within the steam area of the low-pressure cylinder for operating the intermediate valve from the exhaust-valve, and an operating-rod, and connection between said rod and the main and exhaust valves, located outside of the steam area of said valves for the purpose set forth.

In testimony that I claim the foregoing as my invention I have signed my name in presence of two subscribing witnesses.

MAROY L. WHITFIELD. I

Witnesses:

THOS. H. YOUNG, HENRY ORTH, Jr.