Improvements in or relating to Motive Power Engines.
Year: 1890

page_text: Date of Application, 29th Aug., 1890-Accepted, 14th Mar., 1891
COMPLETE SPECIFICATION.
Improvements in or relating to Motive Power Engines.
I, JOHN HEINRICH EICKERSHOFF, of 62, Chase Avenue, W.H., Cincinnati,
Ohio, United States of America, do hereby declare the nature of this invention,
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
This invention relates to compound engines of the multi-cylinder single acting
type; its object being to develop and perfect an engine embodying certain con-
structive principles whereby I am able to attain very desirable results not only in
simplicity and consequent economy of initial construction, resulting in economy of
maintenance, and efficiency in respect to the development of mechanical power,
but also great economy and efficiency in respect to the conservancy of heat,
whereby the working economy of the engine as a driving motor is further
enhanced.
In the illustration of this invention herein exhibited is shown and described a
form and type of engine in which the desirable results above referred to are realized
in the highest degree, that is to say: a three-cylinder engine applying power to
three cranks set one hundred and twenty (120°) degrees apart upon a common
crank-shaft, similar in its general constructive aspect to the engine shown in
Patent No. 4792 dated April 6, 1886, upon which this present invention is in the
nature of an improvement.
It should be premised, however, that the principles of the present invention
may be applied to the cylinders set 120° apart axially, and applying their
power to the same crank also to engines of two or any greater number of
cylinders, having any number of expansions. In said former patented engine,
my correspondent controlled the induction and final eduction of steam by
external valves operated by the motion of the shaft: but in the present
improvement he dispenses with all external valves and valve operating gear, and
utilizes the pistons themselves in connection with suitable ports and passages to
control the steam distribution in respect to induction, cut-off, expansion-over, and
final exhaust, so proportioning and constructing the parts that the "high-
pressure" and "low-pressure" cylinder-spaces are entirely independent in respect
to the distribution of steam, and suffer practically no loss of heat; while, also, the
relative arrangement of connecting passages is such that the compression effected
therein, maintains temperature and enables the initial induction and expansion-over
to be effected without waste or loss.
These and other constructive features of the invention are illustrated in the
accompanying drawings, in which :-
Figure 1 exhibits in side elevation an engine of the type indicated, sectioned
through the cylinders and crank-case in their common axial plane:
Figure 2 a horizontal section taken through the cylinders in the plane of
Figure 1:
Figure 3 a horizontal section taken through the cylinders in the plane y of
Figure 1:
Figure 4 a vertical transverse section taken axially through the central cylinder,
as viewed from the left-hand side of Figure 1:
Figure 5 a view similar to Figure 1, showing the application of the invention to
a "triple" expansion engine:
The nature and constructive features of the invention will be best understood by
reference to the drawings in connection with the following description. As I shall
have occasion to refer to the cylinders and their pistons as arranged in series, it is
more convenient to differentiate all parts, in respect to their position in series, by
[Price T

page_text: the numerals 1, 2, 3 and, as the respective parts are duplicated in each element
of the series, I shall designate similar parts by the same reference letter, applying
the appropriate numeral to distinguish the same in series where necessary. Where
no distinguishing numeral is employed the description will be understood to apply
to the part or parts of any cylinder of the series.
The cylinders are formed, as illustrated in the said former Patent, of two
diameters at successive axial portions; A¹, A², A³ being the smaller, and B¹ B² B³
the larger portions, respectively; preferably cast together as one integral cylinder
in each case; and in the present improvement the three differential cylinders with
the connecting passages and braces hereinafter described, are preferably cast as one
integral piece.
The hollow pedestal or "crank-case," H is also cast entire, with suitable openings
for the shaft and bearings, pitmen-play, etc.; so that the common axial plane of
the cylinders projected will coincide with the axis of the driving-shaft, S, which is
carried through the crank-case, H, from end to end, projecting through bearings in
the end walls of the case.
Each cylinder A B is provided at about mid-length of the smaller or
"high-
pressure" portion A with horizontal opposite side ports, the former of which (a)
in each case extends outwardly into the induction steam-passage, s whence live
steam is received from the boiler; while the latter, (b) extends outwardly into a
passage e, connecting it with a port, d of the adjacent cylinder in series at the level
of and midway between the ports ab of such adjacent cylinder. Thus the passage c¹
connects port 6 of cylinder A¹ with port d² of cylinder A"; passage connects
port of cylinder A² with port d³ of cylinder A3; and passage c³ connects port 6,³
of cylinder A3 with port d₁ of cylinder A¹.
The functions of these ports and their connecting passages requires the co-
operation of the pistons, which are constructed as follows:-The pistons are
plungers CC2 C3 fitting the smaller or "high-pressure" cylinder-spaces A
terminated below the enlargement or heads D1 D2 D3 respectively, fitting the larger
or "low-pressure" cylinder-spaces B the respective portions of each piston being
provided with packing-rings insuring a steam-tight fit.
Each plunger-piston is open below and hollow upward through a portion of its
length and carries a pitman P pivoted within the same connected with its
appropriate crank below. Near the top of each plunger C is a transverse passage e
which in a given vertical position of the plunger registers with and connects the
opposite ports ab already described, of its cylinder through the plunger C whereby
steam from the pipes is permitted to flow through the ports a band plunger-
passage e and thence by the passage to the port d of the adjacent cylinder this
action taking place in consecutive order between the cylinders in series, according
to the movement of the plungers as determined by the described relation of the
cranks.
i
Each plunger C is further provided with an interior passage opening vertically
through the top and also laterally through the side of the plunger at a point below
the passage e in position to register with the cylinder-ports near the upper
terminus of the piston-stroke-being so placed that when at said upper terminus the
side opening stands above the port d-but with its lower edge slightly below and
overlapping the upper edge of the port d.
In the relative crank movements of the pistons, the transverse passage e of one
piston as for example C¹ in series begins to register on the down-stroke with the
ports a thus admitting steam as described to port of cylinder A2 at the instant
when the piston side-opening f is at the position relative to said port above
described, and the piston A is ready to begin its down-stroke. Steam thus
admitted flows upward through the passage 2 into the free upper end of cylinder A2
and drives the piston C2 downward-and the same relative governing action takes
place between the other pistons in consecutive series as indicated.
As the admission of steam begins with the edges of the ports fd overlapping as
indicated it continues (except as controlled by the adjacent governing piston) until

page_text: the port has passed below the port d or practically while the piston is travelling
one and a half times the combined width of the ports. It will thus be apparent
that by properly proportioning the ports and the relative positions of their
horizontal bounding edges, the duration of opening, and point of cut-off may be
finely regulated as desired, by the designer according to the assumed boiler-pressure,
and the load to be imposed on the engine.
The expansion of steam over from a high-pressure to a low-pressure cylinder in
series, is effected by a cylinder-port g opening outward below the receiving port d
in the same relations with the piston opening f at the lower terminus of the piston
stroke as sustained by the port d at the upper terminus. The port g is extended
by a passage to and enters the top of the adjacent low-pressure cylinder B in
series-thus the port g' of cylinder A' is extended by a passage ¹ to cylinder 132
port g2 of cylinder A2 by a passage 2 to cylinder B³ and port g³ of cylinder A3 by
a passage to cylinder B.
་
In the descent of a given piston as C¹ the lateral piston opening f1 registers with
the cylinder-port g' and permits the steam contained in cylinder A after completing
its initial work to expand over through passage into the next adjacent low-
pressure cylinder B2 against the descending piston D2 and between the other
cylinders in series the action is similar.
(The extension of the same principle to further expansions will be described
later, in connection with Figure 5.)
k
The final exhaust of steam from the low-pressure cylinder B, is effected by the
following construction; opposite the cylinder-port in each case, a corresponding
port opening outward into an exhaust passage t which may open into the
atmosphere, or a condenser. The ports of each cylinder are connected at proper
intervals by a transverse passage through the plunger A so placed as to register
therewith when the plunger is near the upper terminus of its stroke. This
registering begins, for example in the plunger A' towards the conclusion of its
upward stroke, at the time when the adjacent low-pressure piston D³ is beginning
its exhaust or up-stroke. The steam is thus exhausted back through the passage ²
port g piston passage and cylinder-port into the exhaust passage; and the
duration and point of closure of the opening are determined for the exhaust in the
same manner as for the induction and cut-off as before explained, but under reversed
conditions that is to say as the cranks are set 120 degrees apart one piston has
completed its down-stroke and begins its return or exhaust-stroke when the adjacent
piston in series is beginning the last one-third of its up-stroke: so that while the
exhausting piston is travelling from the beginning to the end of its exhaust stroke,
its said adjacent piston travels the last third of its up-stroke and the first third of
the succeeding down-stroke, thus covering only the upper-third of its cylinder in
the time occupied by the entire travel of the exhausting piston. The opportunity
thus given for utilizing each piston as a valve for controlling the final eduction of
steam from an adjacent ultimate cylinder of the engine outward clear of the crank-
case without resort to external valve-gear, with the added advantage of compression
in the expansion passages at the end of the exhaust-stroke preparatory to the next
succeeding expansion-over through the same passage and the consequent avoidance
of loss, I have utilized in the present invention.
The compression by the high-pressure pistons is, in consequence of the reduction
or small extent of clearance in the upper end of the high-pressure cylinders A
forced into the receiving piston-passage fto or approximately to the initial boiler
pressure; so that no loss of steam is suffered in the initial charge, and as tem-
perature is a concomitant of pressure, the loss of temperature in the walls of
the passage accruing from the previous expansion-over of steam therein is thus
made good.
In like manner the compression at the up-stroke of the low-pressure pistons is
utilized in the passages to restore both pressure and temperature preparatory
to the succeeding expansion-over. It will thus be seen that the common defect
of expansion engines, to wit: waste due to direct loss in filling connecting

page_text: passages, and indirect loss due to steam contact with cooled walls, is entirely
avoided. Moreover it will be seen that while the high-pressure cylinder carries
an excess of its directly available charge in filling the passage f it is not
a repeated expense of steani (after the first stroke) and yet at each stroke the
low-pressure pistons receive the advantage of the added quantity by expansion;
thereby adding so much to the power exerted on the low-pressure pistons, and
increasing the ratable efficiency of the engine.
The constructive principle thus explained, is peculiarly adapted to extension
to three or more expansions inasmuch as a larger quantity of steam is thus
utilized in an engine of given cylinder area and weight of metal, than in other
constructions, the beneficial effect of which is more apparent, in the successive
expansion cylinders. I am thus enabled to obtain a higher general duty besides.
the numerous other advantages referred to-due to the full conservancy of
heat and elastic pressure, besides obtaining all the mechanical and other advantages
of high piston speed-combined results which so far as I am aware, have not
heretofore been successfully realized.
I prefer to construct the pistons each in two parts, that is to say: the
plunger C is cast complete as one part, and the enlargement D as a separate
part; and these, are "trued up" on the lathe after being bolted together. These
parts are turned to a close but easy sliding fit, and grooved peripherally as
indicated for the reception of split packing rings which it is preferred to con-
struct of cast-iron turned to a diameter very slightly exceeding that of the
cylinder and "sprung" into place.
The construction enables me to attach a small steam-pipe, 7 opening by separate
valves into the upper ends of the low-pressure cylinders B1 B2 B³. I find
it very convenient, as an aid in starting the engine, thus to admit live steam for
a short time directly into the low pressure cylinders; thereby assisting the starting
power, clearing out the water of condensation and warming the walls of the low-
pressure cylinders and expansion passages, and thus bring the engine more speedily
into perfect action.
I have described the fixed portion of the engine, as cast in two main parts, to
wit the cylinders and the crank-case. I may however cast the low-pressure
cylinders as part of the crank-case and make the dividing line at as indicated
by dotted lines in Fig. 1. In either case the three cylinders A are cast entire
as one piece, the cross pipes cs and ht forming braces between the cylinders,
which together with upper cross braces m render the parts secure.
The bearings o of the crank-shaft are attached to and carried in the end walls
of the crank-case and I also give the shaft two intermediate bearings, one at
each side of the central crank. These central bearings are upon detachable cross
braces n carried upon ledges or brackets, n' cast upon the side walls of the crank
case.
The entire crank-shaft I make in three parts, that is to say: the central double
crank is made as one separate piece and forms the connecting link between two
other integral elements into which the crank-shaft is divided. The crank shaft
may be in one piece of forged iron; but I obtain good results from a cast-steel
shaft, constructed in the manner described, inasmuch as the number and arrange-
ment of cranks, and the relation of the bearings to the integral portions of the
shaft, produces an equal distribution of strains and a firm support where most
effective.
The mode of applying the principle of construction herein described, to a triple
expansion engine is illustrated in Figure 5. The cylinders are provided with a
third enlargement, F, and the pistons with a corresponding enlargement E-the
general construction of the engine being otherwise the same except as here
specified. The piston D in such case is extended into a plunger of proper length
and provided with an interior port 9 (corresponding with the port e of the upper
piston A) opening through the top of the piston into the cylinder B and outwardly
through the side of the piston, to register on its down-stroke with an additiona

page_text: passager opening from the side of the cylinder B (now become an intermediate
cylinder) over into the adjacent ultimate cylinder F by which the expansion-over
from cylinder B to cylinder F is permitted. As, in this example the final exhaust
does not take place from the cylinders B the plunger port k is dispensed with and
the exhaust passage t is arranged lower down so as to receive the steam from the
cylinders F.
The final exhaust is obtained by providing a transverse port pin the piston D below
the receiving port the construction in this respect being the same as already
described with regard to the port only transferred from piston C to D. The
preceding descriptions having been so full, further specific description, will be
unnecessary; but it will be obvious that the same principle of construction may be
extended to quadruple or even a greater number of expansions.
Having now particularly described and ascertained the nature of the said inven-
tion, as communicated to me by my foreign correspondent, and in what manner the
same is to be performed, I declare that what I claim is
:-
1. A compound single-acting engine of two or more cylinders wherein the
piston of each cylinder operates as a controlling valve in respect to its adjacent
cylinder in series to effect the induction, expansive distribution, and final exhaust of
steam outward clear of the engine without other valves or valve-operating gear,
substantially as set forth.
2. In a compound engine of the character described, a plunger-piston having a
passage therein for the admission of live steam through the top, in combination
with a cylinder constructed with approximately no clearance space beyond the
stroke-limit, and operative parts arranged to effect compression in said cavity
approximating initial boiler pressure, substantially as and for the purpose set forth.
3. In a multiple-expansion single-acting engine of two or more cylinders, an
exhaust-opening at the receiving end of the ultimate expansion-cylinder; a passage
connecting the same with a port in the side of an adjacent cylinder; a second port
in last named cylinder; and a passage in or through the piston of said last named
cylinder bridging and connecting said last named ports simultaneously at a given
portion of the stroke, substantially as and for the purpose set forth.
4. In a multiple-expansion single-acting engine of two or more cylinders, each
extended by successive enlargements into expansion-cylinders, a port in the side of
the last intermediate expansion cylinder extended by a passage to the receiving end
of an adjacent ultimate expansion-cylinder; a second port at the side of the inter-
mediate expansion-cylinder and a transverse passage in or through the piston
adapted to register with and connect the said two cylinder-ports with the extension
passage on the up-stroke of the piston, substantially as set forth.
5. In a multiple-expansion single-acting engine of two or more main cylinders
each extended by successive enlargements constituting expansion-cylinders, an
expansion-port in the side of a last intermediate expansion-cylinder extended by a
passage to the receiving end of the ultimate enlargement of an adjacent main
cylinder; a plunger-piston in each main cylinder adapted to its successive enlarge-
ments and having a passage in the last intermediate enlargement adapted to
register with said expansion-port and effect the expansion from a last interinediate
expansion-cylinder into an ultimate enlargement of an adjacent main cylinder; on
the up-stroke of the piston; an exhaust-port at the side of said intermediate
expansion-cylinder; and a transverse passage in or through said intermediate
piston-enlargement beyond and in line with the expansion-port or passage therein,
adapted to register with and connect the cylinder expansion-port and the opposite
exhaust-port on the in-stroke of the piston, substantially as set forth.
6. In a double-expansion single-acting engine of two or more main cylinders
cach of two differential diameters having corresponding plunger-pistons operating
a common crank-shaft; a side opening in the high-pressure piston extended within
and through its top; a corresponding side-port in the high-pressure cylinder for
the admission of live steam on the up-stroke through the side opening of the

page_text: piston; a passage connecting said expansion-port with the next adjacent low-
pressure cylinder, a second cylinder-port in the high-pressure cylinder opening to
the exhaust passage and a transverse passage through the high-pressure piston
beneath the steam admission opening adapted to register on the up-stroke with
and connect the expansion-port and exhaust-ports of the cylinder; substantially
as set forth.
7. In a compound engine of the character described, the construction and
arrangement of the cylinders and their connecting passages as shown, whereby
the series of cylinders and passagos may be cast entire as one piece-the passages
forming hollow braces supporting the cylinders in relation to each other, substantially
as set forth.
8. In a compound engine of the character described, the construction and
arrangement of the cylinders and bracing passages cast as one integral part, and the
hollow crank case as a second integral part, the two being secured together to
constitute an entire enclosing and supporting frame of two integral parts,
substantially as shown.
9. In a compound engine of the character described, in combination with a high-
pressure cylinder having a lateral port extended by a passage over to the adjacent
low-pressure cylinder, and an opposite port extended into an exhaust passage,
a plunger-piston having a lateral port extended by a passage through the top and
a second opening below the first extending through the plunger, said piston-passages
arranged to register at or near opposite limits of stroke with the cylinder-ports
and passages for the alternate expansion of steam over into, and final exhaust of
steam from the said adjacent low-pressure cylinder, substantially as set forth.
10. In an engine of the character described, having three cranks, the construction
of the crank-shaft as two integral elements each having a crank intermediate
therein, and the centre crank attached upon the inner projecting ends thereof,
substantially as set forth.
11. In an engine of the character described, the independent live-steam
connection or 'starting pipe" to the low-pressure cylinders substantially as set
forth.
12. In an engine of the character described, the arrangement of the cylinders,
pistons, and expansion passages, whereby the latter are also used in reverse for
the final exhaust of steam, and also for compression of steam therein to restore
temperature and prevent waste in the succeeding expansion, substantially as set
forth.
13. In an engine of the character described wherein the several cylinders open
into the crank-case and the several plunger-pistons are utilized as cross heads for
pitmen pivoted therein and operate also as governing valves for the distribution of
steam to and from each other; the construction and arrangement of parts whereby
the exhaust is wholly outward independently of the crank-case substantially as
set forth.
Dated this 29th day of August 1890.
W. P. THOMPSON & BOULT,
Agents for the Applicant.