Improvements in and relating to Steam Engines.
Year: 1890

page_text: Date of Application, 2nd Dec., 1890 Accepted, 7th
1804
πντεμισα
COMPLETE SPECIFICATION.
Improvements in and relating to Steam Engines.
We, FRANK CAREY, Photographer, and JOHN WESLEY YOUNG, Agent, and
citizens of the United States of America, residing respectively at Penn Yan, in the
County of Yates and State of New York, and at Tunkhannock, in the County of
Wyoming and State of Pennsylvania, and United States of America, do hereby
declare the nature of this invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following state-
ment:-
The engine is or may be of the single or multiple cylinder double acting type,
and may be a multiple expansion engine.
Figure 1 is a top plan of the engine and valve gear.
Figure 2 is an end elevation of the same.
Figure 3 is a section on line e-x, Fig. 1, one valve chest being broken away.
Figure 4 is a central longitudinal section and partial elevation of Fig. 1. Valve
bore shown vertical to better illustrate its working.
Figure 5 is a section through one of the enlarged shaft bearings or face plates.
Figure 6 is a broken detail section showing guide or slide ways and their
connection.
Figure 7 is a diagrammatic perspective of the shaft and cranks.
Figure 8 is a diagram intended to illustrate the operation of the device.
A, indicates the frame of the machine. This frame is of rectangular or other
suitable form in plan, and has cross bars, B, C, which have large boxes, 20 and 21,
to support the face plate bearings of the shaft. The frame has also a cross bar, D,
at one end, which has a brass or bearing 22 for the shaft, 60. The face plates need
not necessarily have bearings, but the shaft may be kept in line by any usual
arrangement of the bearing boxes.
The cylinders, 30 and 40, Figures 1, 2 and 3, are supported on the frame, A, by
flange, E, or in other suitable manner. The cylinder, 30, has a steam chest, 31,
provided with a piston valve, 32, Figures 3 and 4, which valve is hollow to permit
the exhaust steam to pass through it. The steam enters port 33, and as the
valve, 32, slides, the steam is admitted to the cylinder, 30, by ports, 34, and 35,
alternately on opposite sides of the piston, 36. The piston rod, 37, passes through
stuffing box, 38.
The steam chest, valve, and connections thus described are not essentially different
from like parts employed in many double acting engines.
The piston rod, 37, bears a cross-head, 39, which moves in guide or slide ways, 50,
and 51, which guides are preferably bolted or otherwise attached to the head, 30×
of the cylinder 30.
The cylinder, 40, is shown to be a duplicate of cylinder, 30, and has a steam
chest, 41, and valve connection corresponding to those described for cylinder 30.
The piston rod, 47, has a cross-head, 49, which moves in guide ways, 53 and 54,
attached to the cylinder head, 40*.
The slide ways are connected and held by the bolts, 56, and spreaders, 55.
(See Fig. 6.)
The slide ways or guides are thus at the same angle relatively to each other as
the cylinders, and extend across the line of the shaft, 60.
The shaft, 60, has an enlarged bearing piece or face plate, 61, which has a
socket, 62, for a crank pin. The face plate, 61, may be a web, with a counter-
balance piece, 63, at the side opposite the socket 62, to counterbalance the crank.
The shaft, 60*, is practically a continuation of shaft, 60, and has a face plate, 65,
corresponding in all respects with the face plate, 61, and having a socket, 66, in line
with the socket or bearing, 62.

page_text: A compound or quadruple crank is placed between the two face plates, 61 and 65.
This compound crank consists of the bar, F, and two cross-head bearing pins, or
cranks, 70 and 71, extending at opposite sides and at opposite ends thereof.
The cross-head, 39 surrounds a suitable bearing or collar, 74, on crank, 70. The
cross-head, 49 in similar manner surrounds collar or wear piece, 76, on crank, 71.
Cross-head pin, 70, has a rigid arm or web, G, parallel with arm, F, and bearing
on a crank pin, 77, which enters the socket, 62 in face plate, 60.
A similar arm or
web, H, rigid with cross-head bearing pin, 71, has a pin, 78, which enters socket, 66,
in face plate, 65.
The pins, 70 and 71, on which the piston rods have direct bearing must be rigid
both with the bar, F, and with the arms, G, and H, but the pins; 77, and 78, may
be rigid with the face plates, and turn in sockets or bearings in the arms, G, H.
The centres of pins, 77, and 78, are opposite the centre of arm or web, F, and
the arm, G, (from centre to centre of its two crank pins) is equal to the distance
from centre of the shaft, 60 to centre of pin, 77. Consequently the pin, 70, might
by itself have a movement around the pin, 77, being at one time in line with shaft, 60,
and again twice the distance from the centre of said shaft, 60, that the pin, 77, is
from the centre of said shaft. The pins, 77, and 78, may be carried by cranks
instead of plates on the shaft, 60, 60*.
We
We have thus for the piston rod or cross head, 39, a limit of travel of four times
the length of arm, G, (measuring from centre of crank pins) which revolve around
shaft, 60, at a distance from its centre exactly of the length of the arm G.
have a precisely similar limit of movement of piston rod, 47, and its cross head.
But as piston rod, 37, moves at a right angle to the line of movement of rod, 47, the
rod, 37, will be at its most effective position when rod, 47, is on its dead centres,
and rice versa.
Thus one cross-head pin serves as a fulcrum while the other crank
is working at its best leverage, and the pins, 77, 78, are all the time acting on face
plates, 61, and 65, to revolve said plates and the shaft, 60, and 60*, of which the
face plates form a part.
The diagram Figure 8 outlines the movement of parts as understood. The dotted
circle, 1, 2, 3, &c. denotes the movement of driving pins, 77, 78. The dotted
lines, a, a, outline the path of cross head pin, 70, and the line, c, c, the path of the
cross-head pin, 71.
With one cross-head pin, a, on the dead centre, the other at ³, will be in position
to present greatest leverage on the driving crank at 1. The movement of a, to a',
and to, carries driving crank centre from 1 to 2, a¹ to a², and ² to c¹, carries
driving pin from 2 to 3; a² to a³, and c¹ to c, carries driving centre from 3 to 4.
c to c', and a³ to a, carries driving crank to 5. c¹ to c², and a to a', carries crank
pin from 5 to 6. e² to ³, and a³ to a", brings crank pin to 7. The piston 37 has
now made one complete stroke, and piston, 47, two half strokes, and the driving
crank pin has made a half revolution, the parts being in the same relative position
as to the application of power at first, but the pistons moving in opposite directions.
Intermediate positions are indicated on the diagram, which it is believed gives a
correct theoretical explanation of the movement of the cranks.
It will be seen while the cross head bearing of 37 goes from a¹ to a, and back to a',
that the cross head bearing of 47 sweeps clear across the centre of motion from
to c² carrying the crank pin on the dotted circle from 12 to 2. The path of both
crank pins are to be taken as one circle, the distance from 12 to 2 is just half the
distance travelled from ¹ to c². The cross head goes through the same performance
from a to a, carrying crank pins from 3 to 5, while 47 works from e' up to e, and
back to c¹.
From the foregoing it will be understood that the direct coupling of the piston
rods to the driving crank at the cross head bearing permits a very compact
arrangement of parts, and that there is no dead centre as far as the driving crank
pin is concerned.
As both cylinders are supplied with steam from port, 33, sɔ bɔth will exhaust
through the hollow slide valves (one being shown at 32) to exhaust the port 80.

page_text: There is a direct relation between the movement of the slide valves and that of
the pistons, caused by the peculiar valve gear employed.
On the shaft, CO there are two eccentric cylinders, 81 and 101, which are secured
together and may be moved lengthwise of the shaft, 60, being held from turning on
the shaft by a straight spline or key. The movement of the eccentrics is directly
lengthwise of the shaft. The eccentrics are formed from elliptical bodies bored
through eccentrically from end to end, the bore of each being at the side of the
centre, so that the bands will never be exactly concentric with the shaft. (See 101,
Fig. 4.)
The eccentrics are not true cylinders in any section taken from their own surfaces
at right angles. Any such section would be an ellipse. Cut through at exactly
right angles with the shaft upon which they are mounted any section would be a
true circle bored eccentrically every different section would show a different
amount of eccentricity, and the lines of such greatest eccentricity would radiate at
varying degrees from the axis of the shaft.
As shown in Figure 4, the eccentrics are in central position, longitudinally of the
actuating sleeves, 82, and 102, but the rods, 83, and 103, will still give a valve
movement sufficient to move the valve exactly up to the steam admission and to
exhaust the cylinders.
Following now the course of the gear from eccentric, 81, it will be understood
that the sleeve, band or collar, 82, is held between guides, 84 and 85. The rod, 83
connects with crank, 86, which is secured to rock shaft, 87, which rock shaft passes
through suitable packing boxes into the exhaust port or chamber, 80, and is there
provided with a crank, 88, which by a pitman, 89, connects with the slide valve, 32.
The rod, 83, similarly engages the crank, 104, which is connected to a hollow
rock shaft, 105, which surrounds rock shaft, 87. Hollow shaft, 105, passes
through stuffing box, 106, and has a crank, 107, in position to operate the slide
valve in steam chest, 41. Thus the two eccentric sleeves, 81, and 101, control the
movement of the two slide valves.
The eccentrics, 81, and 101, are shifted lengthwise of the shaft, 60, by means of
hand lever, 90, hung at 91, and having a collar, 92, coupled to the eccentrics so as
to permit the eccentrics to rotate independently of the collar. The lever, 90, has a
spring catch, 94, which engages one of the notches in the quadrant bar, 93, to hold
the eccentrics in any adjusted position.
When the eccentric cylinders are adjusted in the middle position with lever, 90,
as in Figure 4, the valves have their minimum travel and such travel of either valve
is exactly with the piston of its accompanying cylinder. This reduced valve
travel opens the exhaust but does not admit steam; owing to the slight lead of the
exhaust ends of valve.
The shifting of the lever, 90, either forward or back produces a corresponding change
in the position of the eccentric cylinders, moving them lengthwise of the shaft, producing
a valve movement if the engine is at a standstill, and giving the valves an increased
travel when in motion and admitting steam to the piston for either forward or reverse
motion. The lever may be thrown far enough to bring any part of the bearing
surfaces of the eccentric cylinders in position to actuate the valves, the graduated
notches of the quadrant holding the lever and the eccentrics in any desired position,
so that steam may be cut off from the piston at any point of the stroke from 0, to
nearly full stroke.
The point of cut off varies with the position of the eccentrics, the ends of the
eccentrics giving valve travel sufficient to admit steam nearly full stroke, but the
point of steam admission and exhaust never varies. Steam, if admitted at all,
being admitted just as the piston has passed its lead point; the exhaust having a
slight lead on the steam.
The modification, Figure 9 is a diagrammatic view of a three cylinder engine,
distorted to show sections of cylinders in the same plane. Figure 11 is a reduced
longitudinal section of the disks and crank, the disks being integral or firmly united.
140, 160, and 180, indicate the cylinders. These may be of different diameters, and

page_text: exhaust one into the other for a triple expansion engine. The pistons, 141, 161, and
181, are connected by piston rods, 142, 162 and 182, to the cross heads, 143, 163,
and 183, which are guided in slide ways, 200.
The cross heads are broad, and carry disks, 201, 202, and 203, which are as one
solid piece and are free to rotate in the cross heads, as they turn as one body upon
a crank or wrist pin. A crank or wrist pin, 204, passes through all these disks, and
by face plate, 205, is rigidly connected to the main shaft, 60%. The disks form a
three-throw eccentric, and with the cross heads are in this case the equivalents of
the compound crank.
Figure 10 is a section showing cylinders 240 and 260 set at quarters in the same
plane, with pistons, 241, and 261, connected to a compound crank. Piston, 241, has
two rods, 242 and 243, connected to a three-throw crank, 300. Piston rod, 262, is
connected to the middle bearing of the same crank. This crank has its ends, 301,
turning in sockets in face plates, 302, of the main shaft, 60%. The cross heads and
slide ways are not shown.
In these modifications it will be understood that the valve gear hereinbefore
described, or other suitable valve gear may be employed.
Many other modifications of the compound crank connection will suggest them-
selves to the intelligent mechanic.
The advantage over a pitman rod is that the connection is short, producing a
compact and light engine, and a considerable advantage in the absence of a dead
point, and in the uniform leverage. Also the absence of rod angles makes each half
stroke invariably equivalent to a quarter turn of the shaft.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. The general arrangement of the cylinders, main shaft, and shaft, with the
pistons and piston rods connected to the shaft by a compound crank or equivalent
connection of substantially the character described.
2. The general arrangement of the cylinders and pistons with respect to the main
shaft, and the cross heads and guides attached to the cylinders and extending across
the line of the shaft, substantially as described.
3. The combination with the main shaft, of a face plate or crank, a compound crank
or equivalent connection therewith, and cylinders, piston, and piston-rod connections
to the crank, whereby pitman rods are dispensed with, substantially in the manner
stated.
4. The divided shaft and its crank or face plate connections, and the cylinders,
pistons, and compound crank connections arranged between the sections of the
divided shaft, substantially as hereinbefore described.
5. The shaft having a plurality of cylinders connected together but arranged
eccentrically with each other and with the shaft, sleeves, collars, and valve shifting
gear operated by said eccentrics, and means for shifting the eccentrics lengthwise of
the shaft to control the valve movement.
6. The general arrangement of the cylinders, pistons, piston-rods, and compound
crank connection to the main shaft, and the shifting eccentrics controlling the valve
gear, substantially as hereinbefore described.
Dated this 1st day of December 1890.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.