A Steam or other Fluid-pressure Engine.
Year: 1891

page_text: Date of Application, 6th Jan., 1891-Accepted, 21st Feb., 1891
COMPLETE SPECIFICATION.
A Steam or other Fluid-pressure Engine.
I, CLINTON ARTHUR TOWER, residing at No. 25, Griswold Street, in the City
of Cleveland, County of Cuyahoga, and State of Ohio, U.S.A., Patternmaker, do
hereby declare the nature of this invention, and in what manner the same is to be
perforined, to be particularly described and ascertained in and by the following
statement:-
My invention relates to improvements in steam engines, of the class known as
double acting engines, having pistons at right angles to each other, and a crank
shaft in the pistons whereby dead centres are overcome and a high speed engine of
uniform and easy movement is obtained.
In the accompanying drawings
Fig. 1 is a side elevation of an engine which embodies my invention, the view
showing particularly the valve operating mechanism.
Fig. 2 is a plan view thereof.
Fig. 3 is a central sectional elevation on line x, a, Fig. 2.
Fig. 4 is a horizontal sectional view on line y, y, Fig. 1.
Fig. 5 is a central sectional elevation on line 2, 2, Fig. 1.
Fig. 6 is a view of the central portion of the casing with, say, the top valve,
shown in Fig. 1, removed and disclosing the shape of the chamber in the casing
and the relation of the top piston and its case to said chamber.
Fig. 7 is a perspective view of one of the four valves.
Fig. 8 is a side elevation of the inner piston cylinder with the pistons at the
sides detached and showing the bearing for the crank shaft in the connection
between the inner pistons.
In the drawings 2 represents the casing, and 3 the base upon which the casing
rests. It will be understood, however, that while a certain position of the engine
is shown here, the position is not material, as the engine will work equally well in
different positions. That is, it might be set on either of what appear here as its
ends, or inverted. It is obvious also, that the respective ends and sides of the
entire structure are duplicates of one another, the two opposite pistons, and the
portions of the casing in which they work being identically the same. Hence,
the pistons at the ends are interchangeable with one another, as also are those at
the sides. The same is true of the valves, all four of which are alike.
The two sides of the casing likewise are the same in construction, and are each
provided with steam passages running at right angles to one another to com-
municate with the chambers at the heads of the respective pistons through the
valves. Hence either side may be used as the supply side for steam, and either as
the exhaust, but when one is used for the supply, the other necessarily becomes the
exhaust side. Thus, for this description I have marked the front as the supply
side with supply pipe S, and distributing channels or passages 4, seen longitudinally
at the centre of the casing in Fig. 4, and vertically in Fig. 5. On the reverse side
is the exhaust pipe or opening E, having exhaust passages 5 shown in Figs. 4 and 5,
leading thereto from the respective steam chambers before the pistons through the
several valves to the exhaust.
The steam passages 4 and 5 angle at the drive shaft, and an enlarged annular
opening is made in the casing at this point, and a corresponding annular groove 7,
is formed in each bearing nut 8 to enable the steam to pass around the nut and
have free flow through the passages. The casing is threaded on either side of the
steam passages, as is also the nut 8 which is threaded on both sides of the groove 7
to engage the casing and form a firm support for the shaft as well as to confine the
steam.

page_text: The casing thus formed is adapted to the use of four pistons, two of which work
horizontally, and two vertically. The horizontal pistons 9, work in close fitting
chambers 10, formed in the main casing, and the pistons 11, work in a cylinder 12,
set into the main casing at right angles to chambers 10. The main casing has an
oval shaped chamber, as plainly seen in Fig. 6, in which the cylinder 12 is adapted
to reciprocate laterally, and has short arms 13, at either side of its centre upon
which the pistons 9 are fixed by long bolts 14, as plainly seen in Fig. 3. If it were
not for the fact of placing the pistons in the casing, the pistons 9 might be cast
integral with the cylinder 12. As it is, the pistons 9 are bolted to the cylinder
after each has been placed separately in its chamber.
It will thus be observed that the cylinder 12 and its attached pistons 9 have a
right and left hand movement together within their respective chambers, and this
movement in either direction is limited by the throw of the crank 15 on the drive
shaft, the relative length of which is shown in Fig. 5. Both ends of the cylinder 12
are confined by the cap and base respectively, and its sides are flattened slightly,
as seen at 16, Fig. 6, to work against the flat faces 17 on the sides of the casing
and keep the cylinder in perfect alignment. Centrally through the sides of the
cylinder 12 are slots, which afford room for the lateral movement of the cylinder
on said shaft, and the crank 15 works inside the cylinder between these slots.
Within the cylinder 12 are the pistons 11 connected by a neck 18, which, in this
instance, is cast solid with the pistons, but may be made separate if preferred.
This neck has a transverse open slot 19, at its centre which forms part of a bearing
for the crank 15, and the bearing is completed by a block 20, fitting in said slot and
provided with a conical hole 21, Fig. 3, which is entered by a screw bolt or plug 22,
having a tapering end to enter said hole and tighten the block in proportion as said:
plug is turned home. The plug 22 passes through the upper or exposed piston, and
the shaft and block are not placed in position until after the cylinder 12 has been
placed in the casing.
Now, having the several pistons arranged as shown and described, the steam
chests or chambers are closed by caps 23 at the end of the casing, and by cap 24 at
the top.
In the present construction the base 3 closes the lower portion of
cylinder 12 and forms a chamber for the lower valve. For the other valves the
caps 23 and 24 are provided with valve chambers. Each of the valves 25 has a
stem 26, projecting from one end through the cap which confines the valve in its
place, and on these stems are fixed short arms 27, provided with set nuts for
convenience of adjustment. Each arm has a rod 28, connected with a common
ring 29, which works on an eccentric 30, on the main shaft, and through which the
movements of the valves are effected. By this mechanism, after the requisite
adjustment of the several valves has been made so that each will open and reverse
at the proper time, the flow of the steam is automatically controlled as in other
engines. To establish the necessary circulation of the steam through the valves,
each valve has a transverse cut or groove 31, across its ends, and two parallel slots
or grooves 32, separated by a narrow partition 33, and each terminating at its outer
end in the transverse cut. The outer edges of each slot are cut down toward one
end, as at 34, Fig. 7, so as to facilitate the flow of the steam. The respective caps
which close the steam cylinders have openings 35, which communicate between the
regular steam ducts 4 and 5 in the main casing and the valve chambers, or, to be
more explicit, with the slots and grooves 31 and 32 in the valve 25.
Then to
complete the steam circulation, each head or cap 23, 24, has a narrow longitudinal
slot 36, which opens a passage between the space in the steam chest before each
piston and the valve and valve chamber, and the steam enters and exhausts
through this slot according as one or the other of the grooves 32 registers there-
with. That is, if the valve be rotated to a certain position, steam will be admitted
through ports or ducts 4, 35, 31, 32, 36, to the steam chest or chamber, and when
said valve is slightly turned to exhaust, the steam will flow out through 36, 32, 31,
35 and 5, to the exhaust pipe, and these channels are the same for the several
valves. The ducts, channels, or chambers for the live steam are further indicated

page_text: by s, and the ducts, channels, or chambers for the dead or exhaust steam by e. As
before stated, however, these respective channels may be reversed if desired, as the
engine will work equally well either way.
Thus constructed, the operation of the machine is as follows; steam being
admitted at the right of the engine and exhausted at the left, say as shown in
Fig. 3, the operating parts will be in the positions as seen in the respective
Figures 1, 2, 3, 4, and 5. Thus positioned, the two pistons 9 and the cylinder 12
by which they are connected, move to the left under pressure of steam on the right
hand piston. This movement will continue carrying the pistons 11 along with
cylinder 12 till the crank 15 approaches the dead centre with respect to the right
hand piston, when the upper valve 25 will begin to open and admit pressure against
the upper piston. Meantime the left hand steam chamber has exhausted, and said
chamber and its valve prepared to admit steam in turn as the crank 15 is carried
down past the dead centre with respect to said piston and chamber. When this
occurs, the right hand valve has rotated sufficiently to open the exhaust, and in all
cases the opposed chambers have their supply and exhaust channels open at the
same time.
That is, when one valve takes steam, the other exhausts steam.
The crank 15 having passed the dead centre at the left, the cylinder 12, with its
attached pistons, will return toward the right with the crank 15 on the down stroke
and under pressure of the expanding steam in the upper cylinder and steam now
appearing in the left hand cylinder. Movement down on the left and around below
past the dead centre follows, when steam in turn enters the lower chamber and
carries the crank 15 past the dead centre on the right, and opposite the respective
pistons 9. Thus steam enters each of the piston chambers in succession at each
The full
quarter revolution of the shaft, and the exhaust is opened in like manner.
head of steam is on each piston in turn as the crank of the drive shaft reaches the
dead centre of the next preceding piston. This gives a sweeping movement to the
steam as it follows the crank round and round and keeps the crank under a
substantially constant and regular pressure, which is the object of the invention.
One of the rods 28 is rigid with the ring 29, to prevent it from turning on the
eccentric while the other rods are pivoted thereon, and the eccentric itself is fixed
on the shaft by a set screw so that the necessary movement of the valves is
imparted by the eccentric turning in the ring.
The idle chamber in which the cylinder 12 moves back and forth furnishes room
and opportunity to oil the interior of the engine.
Suitable packing for the bearing screws 8 around the drive shaft is shown at 37
in Figs. 4 and 5.
In operation the side ports in the casing are constantly filled with live steam, but
this steam is never lost till used.
The valves 25 might be made slightly tapering if desired, but this is not
deemed necessary, as what little steam gets back of them only helps to keep
them down to place. At most their movement is slight, and the direction of
the steam is governed by the position of the partition 33 with respect to slot 36.
Compactness in construction, a continuous movement under constant and even
pressure, and possibility of very high speed are among the advantages of this
invention.
It will be seen that no packing is required between the inner cylinder 12
and the casing, as
no steam can enter the chamber on which said cylinder
works unless it creeps through the packing of the pistons, or at other points,
but of this there is no danger when suitable packing is made. Thus said
cylinder is as free to work in its bearing as if its chamber were open to the
outer air.
°
The slot 36 in the cap 24 on the top of the engine is in line with the axle
of the drive shaft so that it will be open to the corresponding piston at all
times when the valve that controls said slot is in position to admit or exhaust
steam, and the same is true of the slot at the base.

page_text: A peculiar and novel feature of this invention is the enlarged interior chamber
and the cylinder therein carrying two pistons and forming the chambers therefor.
These piston chambers are enclosed around the side by the cylinder, and are
open at the end to the steam, so that the piston is exposed to the steam only
at its front, and nowhere else. The same is true of the side pistons which are
only exposed to the steam on their front, and work closely in chambers at their
sides.
"
It should be understood that though the word " steam is here used as the
means by which the engine is driven, any other means, as gas, compressed
air, or other similar agency which exerts pressure by expansion may be employed.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what 1
claim is :-
1. In a double acting engine, the casing having opposite circular piston chambers,
a cylinder set in said casing at right angles to said chambers and carrying a pair
of pistons working in said piston chambers and a pair of pistons working in said
cylinder at right angles to the aforesaid pistons, all four of said pistons having
equal surfaces exposed to pressure, substantially as described.
2. In a double acting engine, the casing having a hollow interior chamber and
circular piston chambers opposite to one another and of less diameter than said
interior chamber, in combination with a plain cylinder set at right angles to the
axis of the said piston chambers and carrying pistons working in said chambers,
and a pair of connected pistons in the said cylinder, all of said pistons having an
equal area subject to pressure, substantially as described.
3. In a double acting engine, a casing provided with an interior chamber and
cylindrical piston chambers of less diameter than said interior chamber at right
angles to the axis of the drive shaft, in combination with a cylinder set in the
casing intermediate of said piston chambers and with its axis at right angles thereto,
a pair of connected pistons in said cylinder, and a pair of pistons on the sides
thereof and working in said cylindrical chambers, substantially as described.
4. In a double acting engine, the outer cylindrical casing having a chamber in
the centre with flat sides at right angles to the axis of the main shaft, and a
cylinder in said casing having its sides flattened to match the flat sides of the casing,
in combination with pistons upon the outside of said cylinder and inside thereof,
substantially as described.
5. In a double acting engine, a cylinder containing two united pistons free to
reciprocate therein, and having two other pistons on its sides connected to said
cylinder by arms, in combination with a casing having an interior chamber in which
said cylinder works, and two piston chambers on its sides for the pistons on the
outside of the said cylinder, all said pistons having equal pressure area, substan-
tially as described.
6. In a double acting engine, a main casing provided with a hollow interior, a
cylinder in said casing carrying two pistons on its inside and two pistons supported
on arms at its outside and removed from the side of the cylinder by said arms, each
set of pistons being at right angles to the other set, and all of equal area, in com-
bination with a separate valve for each piston, inlet and outlet ducts common to
the several valves, and mechanism operating said valves having a common centre of
movement, substantially as described.
7. In a double acting engine, a casing having steam ducts centering at the
bearing of the drive shaft, in combination with said shaft and a bearing for the
shaft around which the steam passes from one side of the shaft to the other,
substantially as described.
8. In a double acting engine, a casing having an interior chamber and two
piston chambers outside the limits of said chamber and opening into the same, in
combination with a cylinder having arms at its sides carrying pistons working in

page_text: said piston chambers, the opening through said cylinder being at right angles to
said piston chambers, and a pair of connected pistons working in said cylinder,
substantially as described.
9. In a double acting engine, a main casing having an interior chamber and
opposite piston chambers distinct and separate from said chamber but opening
therein, in combination with a cylinder in the interior chamber carrying two pistons
inside at right angles to the other pistons, and a separate valve on the main casing
opposite the face of each piston to control the flow of steam, substantially as
described.
Dated this 15th day of December 1890.
CLINTON ARTHUR TOWER.